Clostridium novyi explained

Clostridium novyi (oedematiens) a Gram-positive, endospore- forming, obligate anaerobic bacteria of the class Clostridia. It is ubiquitous, being found in the soil and faeces. It is pathogenic, causing a wide variety of diseases in humans and animals.

Growth in culture proceeds through 3 stages: Initial growth wherein no toxin is produced; vigorous growth wherein toxin is produced; and spore formation wherein endospores are formed and toxin production decreases. It is suggested that type C may be type B that forms spores more readily so does not go through the toxin-production stage.

Isolating and identifying C novyi is difficult due to its extreme anaerobic nature. Commercial kits may not be adequate.^{[1] [2]}

It is also fastidious and difficult to culture, requiring the presence of thiols.^[3]

Taxonomy

Clostridium novyi is considered to be made up from three clades, labelled A, B and C, distinguished by the range of toxins they produce. While strains of type C were not linked to disease to laboratory animals, presence and activity of toxins in C. novyi have been linked to infection with Bacteriophages.^[4] Based on toxin production, Clostridium haemolyticum has been suggested to be considered a part of C. novyi, forming a separate type D in the genus.^[5] More recent 16S-rDNA studies however have suggested, that C. haemolyticus and types B and C of C. novyi may form a distinct species, closely related to Clostridium botulinum type C and D ("group III"), instead.^[4]

Toxins

The toxins are designated by Greek letters.^[6]

Toxins normally produced by the various types of C novyi

C novyi type	Toxins
A	alpha, gamma, delta, epsilon
B	alpha, beta, zeta
C	gamma

The alpha-toxin of Clostridium botulinum types C and D, is similar to the C novyi beta-toxin.The A and B toxins of Clostridium difficile show homology with the alpha-toxin of C novyi as does the lethal toxin of clostridium sordellii.^[7]

Alpha-toxin

The alpha-toxin is characterised as lethal and necrotizing.

The type A alpha-toxin is oedematising.^[8] It acts by causing morphological changes to all cell types especially endothelial cells by inhibition of signal transduction pathways,^[9] resulting in the breakdown of cytoskeletal structures.^[10] The cells of the microvascular system become spherical and the attachments to neighbouring cells are reduced to thin strings. This results in leakage from the capillaries, leading to oedema. The threshold concentration for this action to occur is 5 ng/ml (5 parts per billion) with 50% of cells rounded at 50 ng/ml.

The duodenum is particularly sensitive to the toxin. Injection into dogs resulted in extreme oedema of the submucosal tissues of the duodenum while leaving the stomach uninjured. Injection into the eye resulted in lesions similar to flame haemorrhages found in diabetic retinopathy.

The toxin is a large 250-kDa protein the active part of which is the NH₂-terminal 551 amino acid fragment.^[11] Alpha-toxins are glycosyltransferases, modifying and thereby inactivating different members of the Rho and Ras subfamily of small GTP-binding proteins.^{[12] [13] [14]} C novyi type A alpha-toxin is unique in using UDP-N-acetylglucosamine rather than UDP-glucose as a substrate.^[15]

Beta-toxin

The beta-toxin is characterised as haemolytic, necrotizing lecithinase.

Gamma-toxin

The gamma-toxin is characterised as haemolytic, lecithinase.

Delta-toxin

The delta-toxin is characterised as oxygen labile haemolysin.

Epsilon-toxin

The epsilon-toxin is characterised as lecithino-vitelin and thought to be responsible for the pearly layer found in cultures.

Zeta-toxin

The zeta-toxin is characterised as haemolysin.

Human diseases

The type and severity of the disease caused depends on penetration of the tissues. The epithelium of the alimentary tract, in general, provides an effective barrier to penetration. However, spores may escape from the gut and lodge in any part of the body and result in spontaneous infection should local anaerobic conditions occur.

Tissue penetration

Wound infection by C novyi and many other clostridium species cause gas gangrene^[16] Spontaneous infection is mostly associated with predisposing factors of hematologic or colorectal malignancies and with diabetes mellitus,^[17] although Gram-negative organisms, including Escherichia coli, may lead to a gas gangrene-like syndrome in diabetic patients. This presents with cellulitis and crepitus, and may be mistaken for gas gangrene.^[18] Spontaneous, nontraumatic, or intrinsic infections from a bowel source have been increasingly reported recently.^[19]

Clostridium novyi has been implicated in mortality among injecting illegal drug users.^{[20] [21]}

Epithelial infections

Symptoms are often non-specific including, colitis, oedematous duodenitis, and fever with somnolence.

Testing is problematical with figures presented by McLauchlin and Brazier [cited above] suggesting a false negative rate of about 40% under ideal conditions. Only positive results may be regarded as reliable. In the absence of a positive test, C. novyi type A may be inferred from characterisation by clinical observation, table 2.

Table 2
Observation	Comment
Oedema	Especially if extreme with rapid onset. In view of the sensitivity of the duodenum to the alpha-toxin, oedematous duodenum is always suspect.
Anaerobic	Infection occurs at an anaerobic site such as the gut or salivary gland. It may also occur at a site temporarily made anaerobic by occlusion and maintained in this state by oedema.
Gram positive	If penicillin causes remission of oedema then a Gram positive organism is the causative agent.

Chronic infection leading to leaky capillaries may also cause retinal haemorrhages and oedema in the lower extremities leading to necrosis and gangrene. Leaky nephrons may compromise the ability of kidneys to concentrate urine leading to frequent urination and dehydration.

Animal diseases

Gas gangrene: infectious necrotic hepatitis (black disease)^[22]

See also

• Clostridium novyi-NT, an attenuated form being studied for its potential use as a cancer treatment

Further reading

• Book: Asferd . Mengesha . Ludwig . Dubois . Kim . Paesmans . Brad . Wouters . Philippe . Lambin . Jan . Theys . Clostridia in Anti-tumour Therapy . https://books.google.com/books?id=RswRaXavXqYC&pg=PA199 . Holger . Brüggemann . Gerhard . Gottschalk . Clostridia: Molecular Biology in the Post-genomic Era . Caister Academic Press . Norfolk, England . 2009 . 199–214 . 978-1-904455-38-7.
• Bettegowda C, Dang LH, Abrams R . Overcoming the hypoxic barrier to radiation therapy with anaerobic bacteria . Proceedings of the National Academy of Sciences of the United States of America . 100 . 25 . 15083–8 . December 2003 . 14657371 . 299912 . 10.1073/pnas.2036598100. 2003PNAS..10015083B . etal. free .
• Groot AJ, Mengesha A, van der Wall E, van Diest PJ, Theys J, Vooijs M . Functional antibodies produced by oncolytic clostridia . Biochemical and Biophysical Research Communications . 364 . 4 . 985–9 . December 2007 . 17971292 . 10.1016/j.bbrc.2007.10.126.
• Dang LH, Bettegowda C, Huso DL, Kinzler KW, Vogelstein B . Combination bacteriolytic therapy for the treatment of experimental tumors . Proceedings of the National Academy of Sciences of the United States of America . 98 . 26 . 15155–60 . December 2001 . 11724950 . 64999 . 10.1073/pnas.251543698. 2001PNAS...9815155D . free .
• St Jean AT, Zhang M, Forbes NS . Bacterial Therapies: Completing the Cancer Treatment Toolbox . Current Opinion in Biotechnology . 19 . 5 . 511–7 . October 2008 . 18760353 . 2600537 . 10.1016/j.copbio.2008.08.004.
• Cruz-Morales . Pablo . Orellana . Camila A . Moutafis . George . Moonen . Glenn . Rincon . Gonzalo . Nielsen . Lars K . Marcellin . Esteban . Revisiting the Evolution and Taxonomy of Clostridia, a Phylogenomic Update . Genome Biology and Evolution . 1 July 2019 . 11 . 7 . 2035–2044 . 10.1093/gbe/evz096 . free. 31076745 . 6656338 .

External links

• Type strain of Clostridium novyi at BacDive - the Bacterial Diversity Metadatabase

Notes and References

1. Brazier JS, Duerden BI, Hall V . Isolation and identification of Clostridium spp. from infections associated with the injection of drugs: experiences of a microbiological investigation team . Journal of Medical Microbiology . 51 . 11 . 985–9 . November 2002 . 12448683 . etal . 10.1099/0022-1317-51-11-985 . free .
2. Book: National Standard Methods . . July 2008 . Identification of Clostridium species . BSOP ID8 Issue 3 . 2010-02-26 . https://web.archive.org/web/20091105154023/http://www.hpa-standardmethods.org.uk/documents/bsopid/pdf/bsopid8.pdf . 2009-11-05 . dead .
3. Moore WB . Solidified media suitable for the cultivation of Clostridium novyi type B . Journal of General Microbiology . 53 . 3 . 415–23 . October 1968 . 5721591 . 10.1099/00221287-53-3-415. free .
4. Sasaki Y, Takikawa N, Kojima A, Norimatsu M, Suzuki S, Tamura Y . Phylogenetic positions of Clostridium novyi and Clostridium haemolyticum based on 16S rDNA sequences . International Journal of Systematic and Evolutionary Microbiology . 51 . Pt 3 . 901–4 . May 2001 . 11411712 . 10.1099/00207713-51-3-901 . free .
5. Oakley CL, Warrack GH, Clarke PH . The toxins of Clostridium oedematiens (Cl. novyi) . Journal of General Microbiology . 1 . 1 . 91–107 . Jan 1947 . 20238541 . 10.1099/00221287-1-1-91. free .
6. 10.1099/00221287-1-1-91 . C. L. . Oakley . G. Harriet . Warrack . 20238541 . Patricia H. . Clarke . The Toxins of Clostridium oedematiens (Cl. novyi). Journal of General Microbiology . 1 . 1 . 1947 . 91–107. free .
7. Hofmann F, Herrmann A, Habermann E, von Eichel-Streiber C . Sequencing and analysis of the gene encoding the alpha-toxin of Clostridium novyi proves its homology to toxins A and B of Clostridium difficile . Molecular & General Genetics . 247 . 6 . 670–9 . June 1995 . 7616958 . 10.1007/BF00290398. 10460632 .
8. Bette P, Frevert J, Mauler F, Suttorp N, Habermann E . Pharmacological and biochemical studies of cytotoxicity of Clostridium novyi type A alpha-toxin . Infection and Immunity . 57 . 8 . 2507–13 . August 1989 . 10.1128/IAI.57.8.2507-2513.1989 . 2744858 . 313478 .
9. Schmidt M, Rümenapp U, Bienek C, Keller J, von Eichel-Streiber C, Jakobs KH . Inhibition of receptor signaling to phospholipase D by Clostridium difficile toxin B. Role of Rho proteins . The Journal of Biological Chemistry . 271 . 5 . 2422–6 . February 1996 . 8576201 . 10.1074/jbc.271.5.2422. 25746652 . free .
10. Müller H, von Eichel-Streiber C, Habermann E . Morphological changes of cultured endothelial cells after microinjection of toxins that act on the cytoskeleton . Infection and Immunity . 60 . 7 . 3007–10 . July 1992 . 10.1128/IAI.60.7.3007-3010.1992 . 1612768 . 257268 .
11. Busch C, Schömig K, Hofmann F, Aktories K . Characterization of the Catalytic Domain of Clostridium novyi Alpha-Toxin . Infection and Immunity . 68 . 11 . 6378–83 . November 2000 . 11035748 . 97722 . 10.1128/IAI.68.11.6378-6383.2000.
12. Just I, Selzer J, Hofmann F, Green GA, Aktories K . Inactivation of Ras by Clostridium sordellii lethal toxin-catalyzed glucosylation . The Journal of Biological Chemistry . 271 . 17 . 10149–53 . April 1996 . 8626575 . 10.1074/jbc.271.17.10149. 31949189 . free .
13. Just I, Selzer J, Wilm M, von Eichel-Streiber C, Mann M, Aktories K . Glucosylation of Rho proteins by Clostridium difficile toxin B . Nature . 375 . 6531 . 500–3 . June 1995 . 7777059 . 10.1038/375500a0. 1995Natur.375..500J . 4334048 .
14. Just I, Wilm M, Selzer J . The enterotoxin from Clostridium difficile (ToxA) monoglucosylates the Rho proteins . The Journal of Biological Chemistry . 270 . 23 . 13932–6 . June 1995 . 7775453 . 10.1074/jbc.270.23.13932. 38311133 . etal. free .
15. Selzer J, Hofmann F, Rex G . Clostridium novyi alpha-toxin-catalyzed incorporation of GlcNAc into Rho subfamily proteins . The Journal of Biological Chemistry . 271 . 41 . 25173–7 . October 1996 . 8810274 . 10.1074/jbc.271.41.25173. 19531499 . etal. free .
16. Hatheway CL . Toxigenic clostridia . Clinical Microbiology Reviews . 3 . 1 . 66–98 . January 1990 . 2404569 . 358141 . 10.1128/CMR.3.1.66.
17. Nagano N, Isomine S, Kato H . Human Fulminant Gas Gangrene Caused by Clostridium chauvoei . Journal of Clinical Microbiology . 46 . 4 . 1545–7 . April 2008 . 18256217 . 2292918 . 10.1128/JCM.01895-07. etal.
18. Web site: Necrotising infections . The British Society for Antimicrobial Chemotherapy . 2009-08-04 . https://web.archive.org/web/20031126044232/http://www.bsac.org.uk/pyxis/Skin%20and%20soft%20tissue%20infections/Necrotising%20infections/Necrotising%20infectionsF.htm . 2003-11-26 . dead .
19. Kornbluth AA, Danzig JB, Bernstein LH . Clostridium septicum infection and associated malignancy. Report of 2 cases and review of the literature . Medicine . 68 . 1 . 30–7 . January 1989 . 2642585 . 10.1097/00005792-198901000-00002. 25810277 . free .
20. Finn SP, Leen E, English L, O'Briain DS . Autopsy findings in an outbreak of severe systemic illness in heroin users following injection site inflammation: an effect of Clostridium novyi exotoxin? . Archives of Pathology & Laboratory Medicine . 127 . 11 . 1465–70 . November 2003 . 14567722 . 10.5858/2003-127-1465-AFIAOO . 2020-11-29 . 2020-12-12 . https://web.archive.org/web/20201212003800/https://meridian.allenpress.com/aplm/article/127/11/1465/62832/Autopsy-Findings-in-an-Outbreak-of-Severe-Systemic . dead .
21. McLauchlin J, Salmon JE, Ahmed S . Amplified fragment length polymorphism (AFLP) analysis of Clostridium novyi, C. perfringens and Bacillus cereus isolated from injecting drug users during 2000 . Journal of Medical Microbiology . 51 . 11 . 990–1000 . November 2002 . 12448684 . etal . 10.1099/0022-1317-51-11-990 . free .
22. Book: Infectious Necrotic Hepatitis (Black disease) . http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm/bc/22808.htm . The Merck Veterinary Manual . 9th . Cynthia M. . Kahn . 2005 . . . 978-0-911910-50-6 . 57355058.