To fully understand the
incredible function of the Oxygen Treatment and Therapy in the human body, the
practitioner, health care professional, and/or inquisitive lay person needs to
familiarize themselves with the functions of a cellular enzyme called
Myeloperoxidase (aka MPO for short), as well as the functions of hypochlorous
In the early 1920’s, Dr.
William F. Koch discovered that all disease states are merely different
manifestations of OXYGEN DEFICIENCIES at the cellular level. He called these
oxygen deficiencies the “Least Common Denominator” in maintaining good health,
which is of course synonymous with PREVENTING disease states from forming in the
first place. Therefore, proper oxygenation via all-natural mineral
precursors should be the 1st and primary goal of cellular nutrition
advocates as well.
As a gifted bio-chemist,
Dr. Koch discovered that combining certain carbonyl-group mineral elements in
vitro quickly produced a unique form of hypochlorous acid that he named “glyoxilide”.
I submit he named this catalyst glyoxilide because when it came in contact with
the carbons in GLUCOSE (aka blood sugar) in vivo (in the body) – massive amounts
of singlet, negatively charged oxygen molecules were produced. In turn, these
oxygen molecules proved to be highly effective in eliminating anaerobic
pathogens (harmful bacteria, viruses, fungi and parasites) from the body in a
completely safe, non-obtrusive, and effective manner.
In 1925, Dr. Edward Carl
Rosenow (who spent over 60 years conducting research at the Mayo Clinic) not
only discovered that rheumatic fever was caused by a streptococcus germ – but
that there are literally millions of tiny micro-organisms continually living and
colonizing in the human body. Each different strain of “bug” causes different
problems and health challenges. Some colonize in the hair and scalp resulting
in dandruff. Others colonize in the mouth causing cavities and gum diseases.
Dr. Rosenow found that
individuals with compromised immune systems were consistently low in blood
oxygen. In turn, these microscopic critters would proliferate and be free to do
such nasty things as: 1) consume the cartilage and sulfur of the joints causing
painful rheumatoid arthritis 2) excrete waste material in the form of
electron-deficient calcium that hardens bones and makes them brittle – and when
lodged in the liver and kidneys would form stones 3) colonize in the lining of
the heart arteries, leaving their excrement on the walls of the arteries in the
form of plaque. 4) colonize in the Central Nervous System (CNS) of the spinal
column and brain, making meals of the myelin sheath nerve coatings thus
short-circuiting the central computer of the brain resulting in ALS, MS, ADHD,
and Alzheimer’s. 5) attack individual cells and enter the cellular membrane,
eventually building cocoons around the DNA-damaged cell; cutting off the
oxygen-carrying blood so that the cell can only live and function as part of
cancerous tumor. Thus, it is safe to say that disruption of the ability of the
cells to produce MPO, HClO, and “glyoxilide” results in low oxygen levels, which
in turn eventually forms a DISEASE STATE.
Dr. Koch quickly learned
that such a simple formula providing powerful, life-giving OXYGEN to the cell
would not only prevent disease states from forming, but had the strong potential
to REVERSE so-called “incurable” disease states as well. So, like any honest
medical professional, Dr. Koch proceeded to test his research and theory – and
the results were immediate and dramatic to say the least. Cancer tumors shrunk
and disappeared, diabetes mellitus vanished, mental disorders reversed, and
viral plagues were eliminated. (See
Sadly, however, Dr. Koch
also became painfully aware that reversing such chronic disease states in such a
permanent manner meant drastically decreased PROFITS in the bank accounts of the
burgeoning PHARMACEUTICAL HOUSES owned and operated primarily by John D.
Rockefeller. It meant that in order for “Big Pharma” to flourish, Dr. Koch’s
research and results must be hidden and discredited at all costs. This is
exactly what happened – and this vitally important NUTRITIONAL PRODUCT was lost
to the world for over 50 years. Untold millions have needlessly suffered and
died horrible deaths in order to enrich a few evil men.
In simple, honest words,
the O.T.T. (Oxygen Treatment and Therapy) produces the mineral catalyst that Dr.
Koch named “glyoxilide”. When taken as instructed, the O.T.T. mineral catalyst
is completely non-toxic and safe. When the catalyst is absorbed into the
bloodstream and encounters carbon/glucose molecules, large amounts of OXYGEN is
indeed created, and harmful NITROGEN is reduced. In turn, the free oxygen
destroys anaerobic bacteria, viruses, yeast, and parasites the way NATURE
intended – through the mechanism of OXIDATION in much the same way as OZONE IN
WATER destroys the same harmful pathogens.
For those wishing to have
more “3rd party” validation of this science and my claims, I am
including a paper authored by Dr. Maureen Petersen, MD, Cecilia Mikita, MD, MPH,
and Javed Sheikh, MD on a condition called Myeloperoxidase (MPO) Deficiency,
(but what should actually be called serum oxygen deficiency) and Wikipedia’s
detailed report on hypochlorous acid. I have highlighted in yellow the more
A. True Ott, PhD, ND
February 20, 2009
Maureen M Petersen, MD,
Fellow in Allergy and Immunology, Walter Reed Army Medical Center Cecilia P Mikita, MD, MPH,
Assistant Professor of Pediatrics and Medicine, Uniformed Services University of
the Health Sciences; Associate Program Director of Allergy-Immunology
Fellowship, Chief of Clinical Services, Staff Allergist/Immunologist, Walter
Reed Army Medical Center; Javed Sheikh,
MD, Assistant Professor of Medicine, Harvard Medical School;
Clinical Director, Division of Allergy and Inflammation, Beth Israel Deaconess
Medical Center; Clinical Director, Center for Eosinophilic Disorders, Beth
Israel Deaconess Medical Center
Updated: Oct 29, 2008
Myeloperoxidase (MPO) is a human
enzyme in the azurophilic granules of neutrophils and in the lysosomes of
monocytes. Its major role is to aid in microbial killing. Although MPO received
little clinical attention until 1966, the enzyme was first isolated in 1941, and
deficiency of MPO was first described in 1954. Some patients with MPO deficiency
have impaired microbial killing, but most are asymptomatic.
The condition was initially believed to be very rare with only 15 cases were
reported before the 1970s. However, modern laboratory techniques have allowed
researchers to discover that MPO deficiency is actually more common than
previously described but without clinical relevance.
Normal function of
MPO, a heme-containing protein,
is found in the azurophilic granules of neutrophils and in the lysosomes of
monocytes in humans; however, monocytes contain only about a third of the MPO
present in neutrophils. When neutrophils become activated during phagocytosis,
they undergo a process referred to as a respiratory burst. This respiratory
burst causes production of superoxide, hydrogen peroxide, and other reactive
oxygen derivatives, which are all toxic to microbes. During respiratory bursts,
granule contents are released into the phagolysosomes and outside the cell,
allowing released contents to come into contact with any microbes present.
Experiments conducted in
the 1960s showed that MPO catalyzes the conversion of hydrogen peroxide and
chloride ions (Cl) into hypochlorous acid.1
Hypochlorous acid is 50 times more potent in microbial killing than hydrogen
also directly chlorinates phagocytosed bacteria; thus, the MPO-hydrogen
peroxide-Cl system seems to have an important role in microbial killing.
Although the exact mechanism by which microbial killing occurs is controversial,
researchers are fairly
certain that MPO is important for the process to optimally occur.
to killing bacteria, the products of the MPO-hydrogen peroxide-Cl system are
believed to play a role in killing fungi, parasites, protozoa, viruses, tumor
cells, natural killer (NK) cells, red cells, and platelets.
The MPO-hydrogen peroxide-Cl system is also believed to be involved in
terminating the respiratory burst, because individuals with MPO deficiency have
prolonged respiratory bursts. It
may play a role in downregulating the inflammatory response by
regulating NK cells, decreasing peptide binding to chemotactic receptors, and
auto-oxidizing and inactivating products of polymorphonuclear leukocytes (PMNs),
such as a1-proteinase inhibitor and chemotaxins.
Other functions of MPO include
tyrosyl radical production and chlorination, generation of tyrosine peroxide,
mediation of the adhesion of myeloid cells via b2-integrins, and oxidation of
serum lipoproteins. MPO may have a role in atherosclerosis. Researchers have
demonstrated that patients with stable coronary artery disease had an increased
cardiovascular risk if plasma MPO levels were elevated.2
A small study demonstrated that MPO deficiency may protect against
MPO may also have a role in carcinogenesis and degenerative neurological
diseases. The understanding of MPO biology remains incomplete; much more remains
to be discovered.
MPO is a dimeric molecule,
consisting of a pair of heavy-chain and light-chain protomers and 2 iron atoms.
MPO is encoded by a single gene located on band 17q22-23. The mature enzyme is
synthesized from a single polypeptide product. Therefore, the expression of the
gene and the synthesis of MPO primarily occurs during the promyelocytic stage of
myeloid development, concurrent with development of the azurophilic granules.
The MPO gene encodes for a
primary translational product, which is glycosylated to yield an enzymatically
inactive precursor, apopro-MPO.
Apopro-MPO reversibly binds to chaperone proteins, calreticulin and calnexin,
during protein maturation. This results in the subsequent binding of heme.4
Heme insertion induces conformational changes in the protein yielding pro-MPO,
an enzymatically active precursor.5
Pro-MPO undergoes several complex conversions and eventually becomes mature MPO
in the azurophilic granules, but the exact mechanisms are still poorly
MPO should be distinguished from
eosinophilic peroxidase (EPO), a different enzyme produced by a different gene.
Although patients with MPO deficiency have decreased MPO activity in the
neutrophils and monocytes, these patients usually have normal levels of EPO in
Pathophysiology of hereditary
Hereditary MPO deficiency was
initially thought to follow the classic autosomal recessive pattern. A number of
genetic mutations resulting in MPO deficiency have been identified, and
many others may still be undiscovered. Researchers now believe that most
patients are compound heterozygotes, which means that they have a different
mutation on each allele, one from each parent. As with several other genetic
diseases, numerous allele combinations can lead to the phenotype of MPO
deficiency, which partially explains the variability of clinical features. Some
mutations result in posttranslational defects; others (which are not yet clearly
defined) seem to cause pretranslational defects, possibly due to structural
alterations in the regulatory parts of the
MPO gene. See Causes for a discussion of individual mutations that
have been identified and their effects.
Some authors have proposed a bigenic model involving the interaction of 2 genes,
such as a production gene and a regulatory gene. Overall, the genetic basis of
this condition is now thought to be quite heterogeneous and complex.
Undoubtedly, much remains to be discovered.
Pathophysiology of acquired
MPO deficiency in acquired cases
is usually transient and generally resolves once the inciting condition
improves. In addition, acquired MPO deficiency is usually partial and involves
only a fraction of the PMNs.6The following conditions
can lead to acquired MPO deficiency:
intoxication - Inhibits heme synthesis (a component of mature MPO)
infection - Secondary to PMN activation and "consumption" of MPO
- Cytotoxic agents and some anti-inflammatory agents such as dapsone,
5-aminosalicylic acid, and sulfapyridine
Disseminated cancers - Probably related to administration of cytostatic
hematologic disorders and neoplasms especially those involving the
maturation of granulocytes:
Acute myeloid leukemia (AML)
Chronic myeloid leukemia (CML)
Refractory megaloblastic anemia
Myelofibrosis with myeloid metaplasia
Microbial killing in
MPO-deficient neutrophils are
normally able to phagocytose most microbes. However, the ability of
MPO-deficient neutrophils to kill bacteria seems impaired to varying
degrees. For organisms such as
Staphylococcus aureus, Serratia species, and Escherichia coli, killing is
initially impaired but then reaches normal levels after a period of time. This
suggests that an apparently slower, alternative mechanism of killing can take
over in MPO-deficient neutrophils.
to kill certain fungi, however, seems completely absent in MPO-deficient
neutrophils. In vitro studies have shown that Candida albicans, Candida krusei, Candida
stellatoidea, and Candida
tropicalis cannot be killed by MPO-deficient PMNs. In contrast, an
MPO-independent mechanism can kill Candida
glabrata, Candida parapsilosis, and Candida pseudotropicalis. Even more interesting is that the
hyphal elements of Aspergillus fumigatus
and C albicans cannot be killed,
but the spores of A fumigatus
and the yeast phase of C albicans
can be killed by an independent mechanism. This leads to the conclusion that
bacterial killing may not necessarily be a problem for patients with MPO
deficiency, but the killing of certain fungi may be a problem, depending on the
severity of the deficiency.
Incidence rates from screening
studies range from 1 case per 1400-2000 population.
One series found the prevalence
of total or subtotal MPO deficiency to be 1 case per 2727 population.7
Prevalence rates in Japan have been reported to be much lower, with one study
finding the prevalence of total and partial deficiency to be 1 case per 57,135
population and 1 case per 17,501 population, respectively.8
Until the 1970s, only 15 cases
of MPO deficiency had been reported worldwide. Because most cases are
asymptomatic, very few people were evaluated for the deficiency. However, modern
laboratory techniques, particularly the wider application of automated flow
cytometry for determining WBC differentials, have allowed the screening of large
study populations to determine the true prevalence of MPO deficiency.7
European researchers evaluated
patients with complete MPO deficiency and found that about half of the patients
had infectious complications; the other half were asymptomatic. Approximately
10% of the cases involved life-threatening infectious complications. Other
studies have reported that severe infections occur in fewer than 5% of patients
with MPO deficiency; however, this frequency may be based on the inclusion of
both complete and partial deficiencies. Generally, infections only occur in
patients who have concomitant diabetes mellitus.
Most individuals with
partial or total myeloperoxidase (MPO) deficiency have no increased
frequency of infections, probably because MPO-independent mechanisms in
the polymorphonuclear leukocytes (PMNs) can take over. In general, it is
considered a relatively benign immunodeficiency and was removed from the
Classification of Primary Immunodeficiency Disease by the Primary
Immunodeficiency Disease Classification Committee of the International
Union of the Immunologic Societies in 2005.
Severe infections are
uncommon, occurring in fewer than 5% of patients with MPO deficiency. If
infectious disease occurs, it is usually a fungal infection
(particularly candidal, such as C albicans or C
tropicalis) that occurs in a patient who also has diabetes
mellitus. Patients without diabetes mellitus rarely have problems,
although the reason for this is unknown. Possibly, MPO deficiency
becomes clinically significant only in the presence of an additional
defect in the host defense, or perhaps the MPO-independent system is
defective in some patients with diabetes mellitus.
entertain the diagnosis of MPO deficiency in cases of invasive fungal
infection in a patient with no known predisposing immune defects (eg,
chemotherapy, corticosteroid treatment) or in a patient with concomitant
diabetes mellitus. Some consider peroxidase staining of the peripheral
blood smear to be part of the complete evaluation of a patient with a
Increased incidence of
A strong association
between total MPO deficiency and malignancies has been reported by
several independent investigators. In vitro, MPO-deficient neutrophils
have decreased destruction of malignant cells demonstrating that the MPO
system plays a central role in tumor surveillance.6
MPO is released from
neutrophils in lung tissue in response to pulmonary insult including
damage secondary to tobacco smoke exposure. MPO has been shown to
convert the metabolites of benzo[a]pyrene from tobacco smoke into a
highly reactive carcinogen. Researchers have demonstrated that decreased
MPO can decrease lung cancer risk.9
Hereditary cases can be
caused by a number of mutations, including R569W, Y173C, M251T, G501S, and
R569W: This is the most
common defect identified to date. Tryptophan is substituted for arginine
at codon 569. Tryptophan cannot form electrostatic bonds. Most patients
described have been compound heterozygotes, but one has been homozygous
for this mutation. The mutation results in a maturational arrest at the
stage of apopro-MPO that is unprocessed, enzymatically inactive, and
undelivered to the azurophilic granules.10
Y173C: Cysteine is
substituted for tyrosine at codon 173. This leads to an additional site
for intramolecular disulfide bonds, which presumably leads to abnormal
folding of the protein. Apopro-MPO is converted into pro-MPO, which is
malfolded. This malfolded pro-MPO seems to be sequestered by calnexin (a
molecular chaperone) and retained in the endoplasmic reticulum. The
trapped precursor then undergoes degradation in the endoplasmic
reticulum. Pro-MPO is prevented from entering the secretory pathway and
cannot proceed to become mature MPO in the azurophilic granules.
Therefore, MPO deficiency resulting from this mutation occurs because of
an abnormality of protein folding. Interestingly, abnormalities in
protein folding have also been described in cystic fibrosis and protein
M251T: In this defect,
mature subunits are formed, but their enzymatic activity is markedly
G501S: This mutation is
a missense mutation within part of the heme-binding pocket. It has been
identified in a Japanese patient with complete MPO deficiency.11
R499C: This mutation is
a nonsynonymous mutation that results in an arginine to cysteine
substitution in the exon 9 coding region. The mutation was identified in
a Japanese patient with complete MPO deficiency. Further genetic
analysis revealed mRNA was transcribed into an appropriate peptide
sequence, but no MPO protein was evident on Western blot findings.12
As time goes on and more
cases are analyzed, more mutations are being identified. Some
pretranslational defects have been described that could be caused by
mutations in the regulatory portion of the MPO gene or by the presence of mutations in other genes
involved in the regulation of the MPO
Acquired MPO deficiency is
less common than the hereditary form. This condition can be transient. The
enzyme defect is corrected when the underlying condition has resolved. In
most cases of acquired deficiency, the deficiency is partial and affects
only a proportion of neutrophils (see Pathophysiology).
Chronic Granulomatous Disease
Glycogen-Storage Disease Type I
Hyperimmunoglobulinemia E (Job) Syndrome
Leukocyte Adhesion Deficiency
Other Problems to Be
Neutropenia (of any cause)
Neutrophil actin dysfunction
Specific granule deficiency
Lazy leukocyte syndrome
Any of the conditions that can cause acquired (secondary) myeloperoxidase (MPO)
The presence of
myeloperoxidase (MPO) can be determined using numerous techniques, including
histochemical staining, immunocytochemistry, and flow cytometry. Depending
on the assay used, one must ensure that eosinophilic peroxidase (EPO) from
eosinophils does not cause false-positive results.
The easiest technique is to
perform direct visualization of neutrophils on a peripheral blood smear that
has been stained for peroxidase. The clinician can ask the pathologist to
examine the neutrophils for peroxidase when a peripheral smear is requested.13
Dihydrorhodamine 123 (DHR)
assay, a flow cytometric assay, is often used to measure the presence of
reactive oxygen intermediates in the work-up of a patient with suspected
immunodeficiency. This assay is easier, more reliable, and more sensitive
than nitroblue tetrazolium dye reduction assay in the diagnosis of chronic
granulomatous disease (CGD). At this time, a DHR assay should not be used as
a screen for MPO deficiency because of variable results and poor sensitivity
in detecting partial MPO deficiency. If a DHR assay is consistent with a
diagnosis of CGD but the clinical history is more consistent with MPO
deficiency, further laboratory testing should be performed (eg, genetic
sequencing or intracellular staining with anti-MPO antibody).14
In general, routine treatment
with prophylactic antibiotics is not recommended because most patients with
myeloperoxidase (MPO) deficiency have no increased incidence of infections.
Exercise caution in patients
with concomitant diabetes mellitus. If infection does occur, initiate prompt
and aggressive treatment with antimicrobials. Every effort should be made to
identify causative agents and administer specific antimicrobial therapy.
If possible, avoid any
treatments that might increase the likelihood of developing fungal infection
(eg, use of broad-spectrum antibiotics, prolonged courses of antibiotics).
See Medical Care.
Inpatient & Outpatient
See Medical Care.
A group from Europe who
studied patients with complete myeloperoxidase (MPO) deficiency found that
about half had infectious complications, while the other half were
asymptomatic. Infectious complications were life threatening in about 10% of
Others have reported severe
infections occurring in fewer than 5% of patients with MPO deficiency (this
frequency may be based on the inclusion of both complete and partial
deficiencies). Infections generally occur only in patients who have
concomitant diabetes mellitus.
Because most patients with
myeloperoxidase (MPO) deficiency do not have serious or life-threatening
infections, failure to diagnose MPO deficiency may have no adverse
consequences. Indeed, because at least half of patients with MPO deficiency
are asymptomatic, most cases are undiagnosed. However, failure to make the
diagnosis in a patient with MPO deficiency with recurrent serious infections
could lead to medicolegal consequences.
If an infectious disease
occurs in a patient with MPO deficiency who also has diabetes mellitus, it
is usually a fungal infection (particularly candidal species such as C albicans or C tropicalis). Patients without
diabetes mellitus rarely have problems. Consider the possibility of MPO
deficiency in a case of invasive fungal infection in a patient with no known
predisposing immune defects (eg, chemotherapy, corticosteroid treatment) or
in a patient with concomitant diabetes mellitus.
1.Dale DC, Boxer L,
Liles WC. The phagocytes: neutrophils and monocytes. Blood. Aug
Braun S, Ndrepepa G, et al. Prognostic value of plasma myeloperoxidase
concentration in patients with stable coronary artery disease. Am Heart J. Feb
3.Kutter D, Devaquet
P, Vanderstocken G, et al. Consequences of total and subtotal myeloperoxidase
deficiency: risk or benefit?. Acta Haematol. 2000;104(1):10-5. [Medline].
WM. Insights into myeloperoxidase biosynthesis from its inherited deficiency. J
Mol Med. Sep 1998;76(10):661-8. [Medline].
WM. Lessons from MPO deficiency about functionally important structural
features. Jpn J Infect Dis. Oct 2004;57(5):S4-5. [Medline].
6.Lanza F. Clinical
manifestation of myeloperoxidase deficiency. J Mol Med. Sep 1998;76(10):676-81. [Medline].
D. Prevalence of myeloperoxidase deficiency: population studies using
Bayer-Technicon automated hematology. J Mol Med. Sep 1998;76(10):669-75. [Medline].
8.Nunoi H, Kohi F,
Kajiwara H, Suzuki K. Prevalence of inherited myeloperoxidase deficiency in
Japan. Microbiol Immunol. 2003;47(7):527-31. [Medline].
9.Taioli E, Benhamou
S, Bouchardy C, et al. Myeloperoxidase G463A polymorphism and lung cancer: a
HuGE genetic susceptibility to environmental carcinogens pooled analysis. Genet
Med. Feb 2007;9:67-73. [Medline].
10.Nauseef WM, Cogley
M, and McCormick S. Effect of the R569W missense mutation on the bio-syn, thesis
of myeloperoxidase. J Biol Chem. Apr 1996;271:9546-9549. [Medline].
11.Ohashi YY, Kameoka
Y, Persad AS, et al. Novel missense mutation found in a Japanese patient with
myeloperoxidase deficiency. Gene. Mar 3 2004;327(2):195-200. [Medline].
12.Persad AS, Kameoka
Y, Kanda S, Niho Y, Suzuki K. Arginine to cysteine mutation (R499C) found in a
Japanese patient with complete myeloperoxidase deficiency. Gene Expr. 2006;13(2):67-71. [Medline].
13.Nauseef WM. How
human neutrophils kill and degrade microbes: an integrated view. Immunol Rev. Oct 2007;219:88-102. [Medline].
14.Mauch L, Lun A,
O'Gorman MRG, et al. Chronic granulomatous disease (CGD) and complete
myeloperoxidase deficiency both yield strongly reduced dihydrorhodamine 123 test
signals but can be easily discerned in routine testing for CGD. Clin Chem. Mar
Blackwood RA. Leukocyte disorders: quantitative and qualitative disorders of the
neutrophil, part 2. Pediatr Rev. Feb 1996;17(2):47-50. [Medline].
16.DeLeo FR, Goedken
M, McCormick SJ, Nauseef WM. A novel form of hereditary myeloperoxidase
deficiency linked to endoplasmic reticulum/proteasome degradation. J Clin
Invest. Jun 15 1998;101(12):2900-9. [Medline]. [Full Text].
Patriarca P, Solero GP, Baralle FE, Romano M. Genetic characterization of
myeloperoxidase deficiency in Italy. Hum Mutat. May 2004;23(5):496-505. [Medline].
Patriarca P, Solero GP, Baralle FE, Romano M. Genetic studies on myeloperoxidase
deficiency in Italy. Jpn J Infect Dis. Oct 2004;57(5):S10-2. [Medline].
19.Milla C, Yang S,
Cornfield DN, et al. Myeloperoxidase deficiency enhances inflammation after
allogeneic marrow transplantation. Am J Physiol Lung Cell Mol Physiol. Oct 2004;287(4):L706-14. [Medline]. [Full Text].
20.Molin L, Stendahl
O. The effect of sulfasalazine and its active components on human
polymorphonuclear leukocyte function in relation to ulcerative colitis. Acta
Med Scand. 1979;206(6):451-7. [Medline].
WM. Myeloperoxidase deficiency. Hematol Oncol Clin North Am. Mar 1988;2(1):135-58. [Medline].
WM. Quality control in the endoplasmic reticulum: lessons from hereditary
myeloperoxidase deficiency. J Lab Clin Med. Sep 1999;134(3):215-21. [Medline].
24.Nauseef WM, Cogley
M, Bock S, Petrides PE. Pattern of inheritance in hereditary myeloperoxidase
deficiency associated with the R569W missense mutation. J Leukoc Biol. Feb 1998;63(2):264-9. [Medline].
Nauseef WM. Molecular and clinical aspects of neutrophil peroxidase deficiency:
multidisciplinary approaches on an international scale. J Mol Med. Sep 1998;76(10):659-60. [Medline].
27.Stendahl O, Molin
L, Dahlgren C. The inhibition of polymorphonuclear leukocyte cytotoxicity by
dapsone. A possible mechanism in the treatment of dermatitis herpetiformis. J
Clin Invest. Jul 1978;62(1):214-20. [Medline]. [Full Text].
Maureen M Petersen, MD, Fellow
in Allergy and Immunology, Walter Reed Army Medical Center
Maureen M Petersen, MD is a member of the following medical societies: American
Academy of Allergy Asthma and Immunology, American Academy of Pediatrics,
American College of Allergy, Asthma and Immunology, American Thoracic Society,
and Clinical Immunology Society
Disclosure: Nothing to disclose
Cecilia P Mikita, MD,
Professor of Pediatrics and Medicine, Uniformed Services University of the
Health Sciences; Associate Program Director of Allergy-Immunology Fellowship,
Chief of Clinical Services, Staff Allergist/Immunologist, Walter Reed Army
Cecilia P Mikita, MD, MPH is a member of the following medical societies:
American Academy of Allergy Asthma and Immunology, American Academy of
Pediatrics, American College of Allergy, Asthma and Immunology, and Clinical
Disclosure: Nothing to disclose
Javed Sheikh, MD, Assistant
Professor of Medicine, Harvard Medical School; Clinical Director, Division of
Allergy and Inflammation, Beth Israel Deaconess Medical Center; Clinical
Director, Center for Eosinophilic Disorders, Beth Israel Deaconess Medical
Javed Sheikh, MD is a member of the following medical societies: American
Academy of Allergy Asthma and Immunology and American College of Allergy, Asthma
Disclosure: UCB Honoraria for Speaking and teaching; Sanofi-Aventis Honoraria
for Speaking and teaching; GlaxoSmithKline Grant/research funds for Clinical
Trial funding; GlaxoSmithKline Consulting fee for Review panel membership;
Novartis Honoraria for Speaking and teaching; Genentech Honoraria for Speaking
and teaching; MedPointe Pharmaceuticals Honoraria for Speaking and teaching
C Lucy Park, MD, Director,
Allergy and Asthma Center, Associate Professor, Department of Pediatrics,
University of Illinois at Chicago
C Lucy Park, MD is a member of the following medical societies: American Academy
of Allergy Asthma and Immunology, American Academy of Pediatrics, American
Medical Association, Clinical Immunology Society, and Illinois State Medical
Disclosure: Nothing to disclose
Mary L Windle, PharmD, Adjunct
Assistant Professor, University of Nebraska Medical Center College of Pharmacy,
Pharmacy Editor, eMedicine
Disclosure: Pfizer Inc Stock for Investment from broker recommendation; Avanir
Pharma Stock for Investment from broker recommendation
David J Valacer, MD, Consulting
Staff, Hoffman La Roche Pharmaceuticals
David J Valacer, MD is a member of the following medical societies: American
Academy of Allergy Asthma and Immunology, American Academy of Pediatrics,
American Association for the Advancement of Science, American Thoracic Society,
and New York Academy of Sciences
Disclosure: Nothing to disclose
David Pallares, MD, Clinical
Assistant Professor, Department of Pediatrics, Division of Allergy and
Immunology, University of Louisville
David Pallares, MD is a member of the following medical societies: American
Academy of Allergy Asthma and Immunology
Disclosure: Nothing to disclose
Harumi Jyonouchi, MD, Associate
Professor, Division of Pulmonary Allergy/Immunology and Infectious Diseases,
Department of Pediatrics, UMDNJ-New Jersey Medical School
Harumi Jyonouchi, MD is a member of the following medical societies: American
Academy of Allergy Asthma and Immunology, American Academy of Pediatrics,
American Association of Immunologists, American Medical Association, Clinical
Immunology Society, New York Academy of Sciences, Society for Experimental
Biology and Medicine, Society for Mucosal Immunology, and Society for Pediatric
Disclosure: Nothing to disclose
biology, hypochlorous acid is generated in activated
neutrophils by myeloperoxidase-mediated peroxidation of chloride ions, and
contributes to the destruction of
bacteriaand this is used in water treatment such as the
acid being the active sanitizer in hypochlorite-based swimming pool products.
aqueous solution, hypochlorous acid partially dissociates into the anion
OCl- + H+
Salts of hypochlorous acid are also
called hypochlorites. One of the best-known hypochlorites is
NaOCl, the active ingredient in bleach.
In the presence of sunlight, hypochlorous acid
hydrochloric acid and
oxygen, so this reaction is sometimes seen as:
+ 2H2O → 4HCl + O2
HClO is considered to be a stronger oxidant
Knox et al.
first noted that HClO is a
sulfhydryl inhibitor that, in sufficient quantity, could completely
inactivate proteins containing
sulfhydryl groups. This is because HClO oxidises
sulfhydryl groups, leading to the formation of
that can result in crosslinking of
proteins. The HClO mechanism of
sulfhydryl oxidation is similar to that of
chloramine, and may only be bacteriostatic, because, once the residual
chlorine is dissipated, some
sulfhydryl function can be restored.
sulfhydryl-containing amino acid can scavenge up to four molecules of HOCl.
Consistent with this, it has been proposed that
sulfhydryl groups of sulfur-containing
amino acids can be oxidized a total of three times by three HClO molecules,
with the fourth reacting with the α-amino group. The first reaction yields
sulfenic acid (R-SOH) then
sulfinic acid (R-SO2H) and finally R-SO3H. Each of
those intermediates can also condense with another
sulfhydryl group, causing cross-linking and aggregation of proteins.
Sulfinic acid and R-SO3H derivatives are produced only at high
molar excesses of HClO, and disulfides are formed primarily at bacteriocidal
Disulfide bonds can also be oxidized by HClO to sulfinic acid.
Because the oxidation of
this process results in the depletion HClO.
protein amino groups
Hypochlorous acid reacts readily with amino
acids that have
amino group side-chains, with the chlorine from HClO displacing a hydrogen,
resulting in an organic chloramine.
amino acids rapidly decompose, but
protein chloramines are longer-lived and retain some oxidative capacity.
Thomas et al.
concluded from their results that most organic chloramines decayed by internal
rearrangement and that fewer available
NH2 groups promoted attack on the
peptide bond, resulting in cleavage of the
protein. McKenna and Davies
found that 10 mM or greater HClO is necessary to fragment proteins in vivo.
Consistent with these results, it was later proposed that the chloramine
undergoes a molecular rearrangement, releasing
ammonia to form an
amide group can further react with another
amino group to form a
Schiff base, causing cross-linking and aggregation of proteins.
Reaction with DNA
Hypochlourous acid reacts slowly with DNA and
RNA as well as all nucleotides in vitro.
GMP is the most reactive because HClO reacts with both the heterocyclic NH
group and the amino group. In similar manner,
TMP with only a heterocyclic NH group that is reactive with HClO is the
CMP, which have only a slowly reactive amino group are less reactive with
UMP has been reported to be reactive only at a very slow rate.
The heterocyclic NH groups are more reactive than amino groups, and their
secondary chloramines are able to donate the chlorine.
These reactions likely interfere with DNA base pairing, and, consistent with
has reported a decrease in viscosity of DNA exposed to HClO similar to that seen
with heat denaturation. The sugar moieties are unreactive and the DNA backbone
is not broken.
NADH can react with chlorinated TMP and UMP as well as HClO. This reaction can
regenerate UMP and TMP and results in the 5-hydroxy derivative of NADH. The
reaction with TMP or UMP is slowly reversible to regenerate HClO. A second
slower reaction that results in cleavage of the pyridine ring occurs when excess
HClO is present. NAD+ is inert to HClO.
exposed to hypochlorous acid lose
viability in less than 100 ms due to inactivation of many vital systems.
Hypochlorous acid has a reported
LD50 of 0.0104 ppm - 0.156 ppm
and 2.6 ppm caused 100% growth inhibition in 5 minutes.
However it should be noted that the concentration required for bactericidal
activity is also highly dependent on bacterial concentration.
In 1948, Knox et
proposed the idea that inhibition of
glucose oxidation is a major factor in the bacteriocidal nature of chlorine
solutions. He proposed that the active agent or agents diffuse across the
cytoplasmic membrane to inactivate key
enzymes in the
glycolytic pathway. This group was also the first to note that chlorine
solutions (HOCl) inhibit
enzymes. Later studies have shown that, at bacteriocidal levels, the
cytosol components do not react with HOCl.
In agreement with this, McFeters and Camper
enzyme that Knox et al.
proposes would be inactivated, was unaffected by HOCl
in vivo. It has been further shown that loss of
sulfhydryls does not correlate with inactivation.
That leaves the question concerning what causes inhibition of
glucose oxidation. The discovery that HOCl blocks induction of
β-galactosidase by added
led to a possible answer to this question. The uptake of radiolabeled substrates
by both ATP hydrolysis and proton co-transport may be blocked by exposure to
HOCl preceding loss of viability.
From this observation, it proposed that HOCl blocks uptake of nutrients by
inactivating transport proteins.
The question of loss of glucose oxidation has been further explored in terms of
loss of respiration. Venkobachar et al.
found that succinic dehydrogenase was inhibited in vitro by HOCl, which led to
the investigation of the possibility that disruption of
electron transport could be the cause of bacterial inactivation. Albrich et
subsequently found that HOCl destroys
iron-sulfur clusters and observed that oxygen uptake is abolished by HOCl
and adenine nucleotides are lost. Also observed was, that irreversible oxidation
cytochromes paralleled the loss of respiratory activity. One way of
addressing the loss of oxygen uptake was by studying the effects of HOCl on
Rosen et al.
found that levels of reductable
cytochromes in HOCl-treated cells were normal, and these cells were unable
to reduce them. Succinate dehydrogenase was also inhibited by HOCl, stopping the
flow of electrons to oxygen. Later studies
revealed that Ubiquinol oxidase activity ceases first, and the still-active
cytochromes reduce the remaining quinone. The
cytochromes then pass the
oxygen, which explains why the
cytochromes cannot be reoxidized, as observed by Rosen et al.
However, this line of inquiry was ended when Albrich et al.
found that cellular inactivation precedes loss of respiration by using a flow
mixing system that allowed evaluation of viability on much smaller time scales.
This group found that
cells capable of respiring could not divide after exposure to HOCl.
Having eliminated loss of respiration Albrich
proposes that the cause of death may be due to metabolic dysfunction caused by
depletion of adenine nucleotides. Barrette et al.
studied the loss of adenine nucleotides by studying the energy charge of
HOCl-exposed cells and found that cells exposed to HOCl were unable to step up
their energy charge after addition of nutrients. The conclusion was that exposed
cells have lost the ability to regulate their adenylate pool, based on the fact
that metabolite uptake was only 45% deficient after exposure to HOCl and the
observation that HOCl causes intracellular ATP hydrolysis. Also confirmed was
that, at bacteriocidal levels of HOCl, cytosolic components are unaffected. So
it was proposed that modification of some membrane-bound protein results in
extensive ATP hydrolysis, and this, coupled with the cells inability to remove
AMP from the cytosol, depresses metabolic function. One protein involved in loss
of ability to regenerate ATP has been found to be
Much of this research on respiration reconfirms the observation that relevant
bacteriocidal reactions take place at the cell membrane.
Inhibition of DNA
Recently it has been proposed that bacterial
inactivation by HOCl is the result of inhibition of
DNA replication. When bacteria are exposed to HOCl, there is a precipitous
DNA synthesis that precedes inhibition of
protein synthesis, and closely parallels loss of viability.
During bacterial genome replication, the
origin of replication (oriC in E. coli) binds to proteins that are
associated with the cell membrane, and it was observed that HOCl treatment
decreases the affinity of extracted membranes for oriC, and this decreased
affinity also parallels loss of viability. A study by Rosen et al
compared the rate of HOCl inhibition of DNA replication of plasmids with
different replication origins and found that certain plasmids exhibited a delay
in the inhibition of replication when compared to plasmids containing oriC.
Rosen’s group proposed that inactivation of membrane proteins involved in DNA
replication are the mechanism of action of HOCl.
abcd Morris, J.
C. (1966), "The acid ionization constant of HClO from 5 to 35 °",
J. Phys. Chem.70: 3798–3805
abcde Fair, G. M., J. Corris, S. L. Chang, I. Weil,
and R. P. Burden. 1948. The behavior of chlorine as a water disinfectant. J.
Am. Water Works Assoc. 40:1051-1061.
Unangst, P. C. "Hypochlorous Acid" in Encyclopedia of Reagents for Organic
Synthesis (Ed: L. Paquette) 2004, J. Wiley & Sons, New York. DOI:
Harrison, J. E., and J. Schultz. 1976. Studies on the chlorinating activity
of myeloperoxidase. Journal of Biological Chemistry volume 251,
abc Thomas, E. L. 1979. Myeloperoxidase, hydrogen
peroxide, chloride antimicrobial system: Nitrogen-chlorine derivatives of
bacterial components in bactericidal action against Escherichia coli.
Infect. Immun. 23:522-531.
abcd Albrich, J. M., C. A. McCarthy, and J. K.
Hurst. 1981. Biological reactivity of hypochlorous acid: Implications for
microbicidal mechanisms of leukocyte myeloperoxidase. Proc. Natl. Acad. Sci.
abc Dennis, W. H., Jr, V. P. Olivieri, and C. W.
Krusé. 1979. The reaction of nucleotides with aqueous hypochlorous acid.
Water Res. 13:357-362.
Jacangelo, J. G., and V. P. Olivieri. 1984. Aspects of the mode of action of
monochloramine. In R. L. Jolley, R. J. Bull, W. P. Davis, S. Katz, M. H.
Roberts, Jr., and V. A. Jacobs (ed.), Water Chlorination, vol. 5. Lewis
Publishers, Inc., Williamsburg.
abcde Prütz, W. A. 1998. Interactions of
hypochlorous acid with pyrimidine nucleotides, and secondary reactions of
chlorinated pyrimidines with GSH, NADPH, and other substrates. Arch.
Biochem. Biophys. 349:183-191.
abc Arnhold, J., O. M. Panasenko, J. Schiller, Y.
A. Vladimirov, and K. Arnold. 1995. The action of hypochlorous acid on
phosphatidylcholine liposomes in dependence on the content of double bonds.
Stoichiometry and NMR analysis. Chem. Phys. Lipids 78:55-64.
abc Carr, A. C., J. V. D. Berg, and C. C.
Winterbourn. 1996. Chlorination of cholesterol in cell membranes by
hypochlorous acid. Arch. Biochem. Biophys. 332:63-69.
ab Domigan, N. M., M. C. M. Vissers, and C. C.
Winterbourn. 1997. Modification of red cell membrane lipids by hypochlorous
acid and haemolysis by preformed lipid chlorhydrins. Redox Rep. 3:263-271.
abc Hazell, L. J., J. V. D. Berg, and R. Stocker.
1994. Oxidation of low density lipoprotein by hypochlorite causes
aggregation that is mediated by modification of lysine residues rather than
lipid oxidation. Biochem. J. 302:297-304.
abc Hazen, S. L., F. F. Hsu, K. Duffin, and J. W.
Heinicke. 1996. Molecular chlorine generated by the myeloperoxidase-hydrogen
peroxide-chloride system of phagocytes converts low density lipoprotein
cholesterol into a family of chlorinated sterols. J. Biol. Chem.
Vissers, M. C. M., A. C. Carr, and A. L. P. Chapman. 1998. Comparison of
human red cell lysis by hypochlorous acid and hypobromous acids: insights
into the mechanism. Biochem. J. 330:131-138.
ab Vissers, M. C. M., A. Stern, F. Kuypers, J.
V. D. Berg, and C. C. Winterbourn. 1994. Membrane changes associated with
lysis of red blood cells by hypochlorous acid. Free Rad. Biol. Med.
Winterbourne, C. C., J. V. D. Berg, E. Roitman, and F. A. Kuypers. 1992.
Chlorhydrin formation from unsaturated fatty acids reacted with hypochlorous
acid. Arch. Biochem. Biophys. 296:547-555.
abcd Barrette, W. C., Jr., D. M. Hannum, W. D.
Wheeler, and J. K. Hurst. 1989. General mechanism for the bacterial toxicity
of hypochlorous acid: Abolition of ATP production. Biochemistry
abc Jacangelo, J. G., V. P. Olivieri, and K.
Kawata. 1987. Oxidation of sulfhydryl groups by monochloramine. Water Res.
abcde Knox, W. E., P. K. Stumpf, D. E. Green, and
V. H. Auerbach. 1948. The inhibition of sulfhydryl enzymes as the basis of
the bactericidal action of chlorine. J. Bacteriol. 55:451-458.
Vissers, M. C. M., and C. C. Winterbourne. 1991. Oxidative Damage to
Fibronectin. Arch. Biochem. Biophys. 285:53-59.
abc Winterbourne, C. C. 1985. Comparative
reactivities of various biological compounds with myeloperoxidase-hydrogen
peroxide-chloride, and similarity to the oxidant to hypochlorite. Biochim.
Biophys. Acta 840:204-210.
ab Pereira, W. E., Y. Hoyano, R. E. Summons, V.
A. Bacon, and A. M. Duffield. 1973. Chlorination studies: II. The reaction
of aqueous hypochlorous acid with a - amino acids and dipeptides. Biochim.
Biophys. Acta 313:170-180.
Dychdala, G. R. 1991. Chlorine and chlorine compounds, p. 131-151. In S. S.
Block (ed.), Disinfection, Sterilization and Preservation. Lea & Febiger,
abc McKenna, S. M., and K. J. A. Davies. 1988.
The inhibition of bacterial growth by hypochlorous acid: possible role in
the bactericidal activity of phagocytes. Biochem. J. 254:685-692.
S. L., A. d'Avignon, M. M. Anderson, F. F. Hsu, and J. W. Heinicke. 1998.
Human neutrophils employ the myeloperoxidase-hydrogen peroxide-chloride
system to oxidize α-amino acids to a family of reactive aldehydes. J. Biol.
abcde Prütz, W. A. 1996. Hypochlorous acid
interactions with thiols, nucleotides, DNA and other biological substrates.
Arch. Biochem. Biophys. 332:110-120.
Rakita, R. M., B. R. Michel, and H. Rosen. 1990. Differential inactivation
of Escherichia coli membrane dehydrogenases by a myeloperoxidase-mediated
antimicrobial system. Biochemistry 29:1075-1080.
ab Rakita, R. M., B. R. Michel, and H. Rosen.
1989. Myeloperoxidase-mediated inhibition of microbial respiration: Damage
to Escherichia coli ubiquinol oxidase. Biochemistry 28:3031-3036.
H., and S. J. Klebanoff. 1985. Oxidation of microbial iron-sulfur centers by
the myeloperoxidase-H2O2-halide antimicrobial system. Infect. Immun.
abc Rosen, H., R. M. Rakita, A. M. Waltersdorph,
and S. J. Klebanoff. 1987. Myeloperoxidase-mediated damage to the succinate
oxidase system of Escherichia coli. J. Biol. Chem. 242:15004-15010.
Chesney, J. A., J. W. Eaton, and J. R. Mahoney, Jr. 1996. Bacterial
glutathione: a sacrificial defense against chlorine compounds. J. Bacteriol.
ab McFeters, G. A., and A. K. Camper. 1983.
Enumeration of indicator bacteria exposed to chlorine. Adv. Appl. Microbiol.
abc Barrette, W. C., Jr., J. M. Albrich, and J.
K. Hurst. 1987. Hypochlorous acid-promoted loss of metabolic energy in
Escherichia coli. Infect. Immun. 55:2518-2525.
Camper, A. K., and G. A. McFeters. 1979. Chlorine injury and the enumeration
of waterborne coliform bacteria. Appl. Environ. Microbiol. 37:633-641.
Venkobachar, C., L. Iyengar, and A. V. S. P. Rao. 1975. Mechanism of
disinfection. Water Res. 9:119-124.
J. L., W. C. Barrette, Jr., B. R. Michel, and H. Rosen. 1991. Hypochlorous
acid and myeloperoxidase-catalyzed oxidation of
iron-sulfur clusters in bacterial respiratory dehydrogenases. Eur. J.
H., and S. J. Klebanoff. 1982. Oxidation of Escherichia coli iron centers by
myeloperoxidase-mediated microbicidal system. J. Biol. Chem. 257:13731-13735
H., J. Orman, R. M. Rakita, B. R. Michel, and D. R. VanDevanter. 1990. Loss
of DNA-membrane interactions and cessation of DNA synthesis in
myeloperoxidase-treated Escherichia coli. Proc. Natl. Acad. Sci. USA
H., B. R. Michel, D. R. vanDevanter, and J. P. Hughes. 1998. Differential
effects of myeloperoxidase-derived oxidants on Escherichia coli DNA
replication. Infect. Immun. 66:2655-2659.