Helicobacter

Helicobacter
Scanning electron micrograph of Helicobacter bilis bacteria
Scientific classification
Domain:	Bacteria
Kingdom:	Pseudomonadati
Phylum:	Campylobacterota
Class:	"Campylobacteria"
Order:	Campylobacterales
Family:	Helicobacteraceae
Genus:	Helicobacter Goodwin et al. 1989 [1]
Type species
Helicobacter pylori (Marshall et al. 1985) Goodwin et al. 1989
Species
See text
Synonyms
"Gastrospirillum" McNulty et al. 1989

Helicobacter is a genus of gram-negative bacteria possessing a characteristic helical shape. They were initially considered to be members of the genus Campylobacter , but in 1989, Goodwin et al. published sufficient reasons to justify the new genus name Helicobacter. ^[2] The genus Helicobacter contains about 35 species. ^{[3] [4] [5]}

Some species have been found living in the lining of the upper gastrointestinal tract, as well as the liver of mammals and some birds. ^[6] The most widely known species of the genus is H. pylori , which infects up to 50% of the human population. ^[5] It also serves as the type species of the genus. Some strains of this bacterium are pathogenic to humans, as they are strongly associated with peptic ulcers, chronic gastritis, duodenitis, and stomach cancer.

Helicobacter species are able to thrive in the very acidic mammalian stomach by producing large quantities of the enzyme urease, which locally raises the pH from about 2 to a more biocompatible range of 6 to 7. ^[7] Bacteria belonging to this genus are usually susceptible to antibiotics such as penicillin, are microaerophilic (optimal oxygen concentration between 5 and 14%) capnophiles, and are fast-moving with their flagella. ^{[8] [9]}

Molecular signatures

Comparative genomic analysis has led to the identification of 11 proteins that are uniquely found in the Helicobacteraceae. Of these proteins, seven are found in all species of the family, while the remaining four are not found in any Helicobacter strains and are unique to Wollinella. Additionally, a rare genetic event has led to the fusion of the rpoB and rpoC genes in this family, which is characteristic of them. ^[10]

Non-H. pylori species

Recently, new gastric (H. suis and H. baculiformis) and enterohepatic (H. equorum) species have been reported. H. pylori is of primary importance for medicine, but non-H. pylori species, which naturally inhabit mammals (except humans) and birds, have been detected in human clinical specimens. These encompass two (gastric and enterohepatic) groups, showing different organ specificity. Importantly, some species, such as H. hepaticus, H. mustelae, and probably H. bilis, exhibit carcinogenic potential in animals. They harbour many virulence genes and may cause diseases not only in animals, but also in humans. Gastric species such as H. suis (most often), H. felis, H. bizzozeronii, and H. salomonis have been associated with chronic gastritis and peptic ulcers in humans, and importantly, with higher risk for MALT lymphoma compared to H. pylori.

Enterohepatic species e.g., H. hepaticus,H. bilis, and H. ganmani, have been detected by PCR, but still are not isolated from specimens of patients with hepatobiliary diseases. Moreover, they may be associated with Crohn's disease and ulcerative colitis. The significance of avian helicobacters (H. pullorum, H. anseris, and H. brantae) also has been evaluated extensively. H. cinaedi and H. canis can cause severe infections, mostly in immunocompromised patients with animal exposure. Briefly, the role of these species in veterinary and human medicine is increasingly recognised. Several other topics such as isolation of still uncultured species, antibiotic resistance, and treatment regimens for infections and pathogenesis and possible carcinogenesis in humans should be evaluated. ^[3]

H. heilmannii sensu lato

Helicobacter heilmannii sensu lato (i.e. H. heilmanni s.l.) is a grouping of non-H. pyloriHelicobacter species that take as part of their definition a similarity to H. pylori in being associated with the development of stomach inflammation, stomach ulcers, ^[11] duodenum ulcers, ^[12] stomach cancers that are not lymphomas, and extranodal marginal B cell lymphoma of the stomach in humans and animals. ^[11] Most clinical studies have not identified the exact species of H. heilmanii associated with these diseases, so designated these species as H. heilmanni s.l. However, investigative studies have identified these species in some patients with the cited H. heilmanni s.l.-associated upper gastrointestinal tract diseases. The H. heilmani species identified to date in the stomachs of humans with the cited upper gastrointestinal tract diseases are: Helicobacter bizzozeronii, Helicobacter felis, Helicobacter salomonis, Helicobacter suis , and Helicobacter heilmannii s.s. ^[11] It is important to recognize the association of H. heilmannii sensu lato with these upper gastrointestinal tract diseases, particularly extranodal marginal zone lymphoma of the stomach, because some of them have been successfully treated using antibiotic-based drug regimens directed against the instigating H. heilmannii sensu lato species. ^[13] The H. heilmanni s.l.-associated human diseases appear to be acquired from pets and farm animals, so are considered to be zoonotic diseases. ^[11]

Phylogeny

The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN) ^[1] and National Center for Biotechnology Information (NCBI) ^[14]

16S rRNA based LTP_10_2024 [15] [16] [17]

120 marker proteins based GTDB 09-RS220 [18] [19] [20]

Wolinella Helicobacter H. anseris H. anatolicus H. mustelae H. kayseriensis H. pametensis H. brantae H. cholecystus H. valdiviensis H. turcicus H. ibisLopez-Cantillo et al. 2023 H. ganmani H. mesocricetorum H. rodentiumShen et al. 1997 H. equorumMoyaert et al. 2007 H. kumamotonensisKawamura et al. 2023 H. pullorumStanley et al. 1995 H. canadensisFox et al. 2002 H. colisuis H. acinonychis H. pylori H. cetorum H. delphinicolaSegawa et al. 2021 H. suis H. labacensis H. bizzozeronii H. cynogastricus H. felis H. salomonis H. heilmannii H. vulpis H. mehlei H. ailurogastricus H. baculiformis H. apriZanoni et al. 2016 H. mastomyrinusShen et al. 2006 H. himalayensis H. didelphidarum H. monodelphidisShen et al. 2020 H. macacae H. marmotae H. jaachi H. saguini H. aurati H. fennelliae H. trogontum H. enhydrae H. hepaticus H. typhlonius H. japonicus H. muridarum H. canis H. bilis H. canicolaKawamura et al. 2016 H. cinaedi

Wolinella Pseudohelicobacter Helicobacter turcicusAydin et al. 2022 "Helicobacter winghamensis" Melito et al. Helicobacter ganmaniRobertson et al. 2001 "P. rodentium" (Shen et al. 1997) Waite, Chuvochina & Hugenholtz 2019 "Helicobacter burdigaliensis" Berthenet et al. 2019 Helicobacter valdiviensisCollado, Jara & Gonzalez 2014 Helicobacter apodemusJeon et al. 2015 Helicobacter mesocricetorumSimmons et al. 2000 "P. pullorum" (Stanley et al. 1995) Waite, Chuvochina & Hugenholtz 2019 "P. canadensis" (Fox et al. 2002) Waite, Chuvochina & Hugenholtz 2019 Helicobacter colisuisGruntar et al. 2022 Helicobacter H. auratiPatterson et al. 2002 H. muridarum Lee et al. 1992 H. saguiniShen et al. 2017 H. didelphidarumShen et al. 2020 H. trogontum Mendes et al. 1996 H. bilis Fox et al. 1997 "H. rappini" Dewhirst et al. 2000 H. enhydraeShen et al. 2020 H. kayseriensisAydin et al. 2022 H. pametensis Dewhirst et al. 1994 H. brantae Fox et al. 2006 "Ca. H. avistercoris" Gilroy et al. 2021 H. cholecystus Franklin et al. 1997 "Ca. H. avicola" Gilroy et al. 2021 H. himalayensisHu et al. 2015 H. jaachiShen et al. 2017 "H. labetoulli" Berthenet et al. 2019 H. cinaedi (Totten et al. 1988) Vandamme et al. 1991 "H. magdeburgensis" Traverso et al. 2010 H. hepaticus Fox et al. 1994 H. marmotaeFox et al. 2006 H. japonicuscorrig. Shen et al. 2017 H. typhlonius Franklin et al. 2002 H. anseris Fox et al. 2006 H. anatolicusAydin et al. 2023 H. mustelae(Fox et al. 1988) Goodwin et al. 1989 H. fennelliae(Totten et al. 1988) Vandamme et al. 1991 H. canis Stanley et al. 1994 H. macacaeFox et al. 2013 H. cetorum Harper et al. 2006 H. acinonychis corrig. Eaton et al. 1993 H. pylori (Marshall et al. 1985) Goodwin et al. 1989 H. bizzozeronii Hanninen et al. 1996 H. mehleiGruntar et al. 2020 H. suis Baele et al. 2008 H. ailurogastricusJoosten et al. 2017 H. heilmanniiSmet et al. 2012 H. cynogastricusVan den Bulck et al. 2006 H. felis Paster et al. 1991 H. salomonis Jalava et al. 1997 H. labacensisGruntar et al. 2020 H. baculiformisBaele et al. 2008 H. vulpisGruntar et al. 2020

Species incertae sedis:

• "Ca. H. bovis" De Groote et al. 1999
• "H. callitrichis" Won et al. 2007
• "Ca. H. cebus" Gueneau de Novoa et al. 2001a
• "H. higonensis" Tomida et al. 2024
• "H. muricola" Won et al. 2002
• "H. peregrinus" Coldham et al. 2004
• "H. suncus" Goto et al. 1998
• "H. tursiopsae" Gueneau de Novoa et al. 2001b
• "H. vulpecula" Coldham et al. 2004

See also

• List of bacterial orders
• List of bacteria genera

References

1. A.C. Parte; et al. "Helicobacter". List of Prokaryotic names with Standing in Nomenclature (LPSN). Retrieved 9 September 2023.
2. Goodwin CS, Armstrong JA, Chilvers T, et al. (1989). "Transfer of Campylobacter pylori and Campylobacter mustelae to Helicobacter gen. nov. as Helicobacter pylori comb. nov. and Helicobacter mustelae comb. nov., respectively". Int. J. Syst. Bacteriol. 39 (4): 397–405. doi: 10.1099/00207713-39-4-397 .
3. Boyanova, L, ed. (2011). Helicobacter pylori. Caister Academic Press. ISBN   978-1-904455-84-4.
4. Vandamme P, Falsen E, Rossaq R, et al. (1991). "Revision of Campylobacter, Helicobacter, and Wolinella taxonomy: emendation of generic descriptions and proposal of Arcobacter gen. nov". Int. J. Syst. Bacteriol. 41 (1): 88–103. doi: 10.1099/00207713-41-1-88 . PMID   1704793.
5. Yamaoka, Y., ed. (2008). Helicobacter pylori: Molecular Genetics and Cellular Biology. Caister Academic Press. ISBN   978-1-904455-31-8. .
6. Ryan, KJ; Ray, CG, eds. (2004). Sherris Medical Microbiology (4th ed.). McGraw Hill. ISBN   0-8385-8529-9.
7. Dunn BE, Cohen H, Blaser MJ (1 October 1997). "Helicobacter pylori". Clin Microbiol Rev. 10 (4): 720–741. doi:10.1128/cmr.10.4.720. PMC   172942 . PMID   9336670.
8. Hua JS, Zheng PY, Ho B (1999). "Species differentiation and identification in the genus of Helicobacter". World Journal of Gastroenterology . 5 (1): 7–9. doi: 10.3748/wjg.v5.i1.7 . PMC   4688506 . PMID   11819372.
9. Rust; et al. (2008). "Helicobacter Flagella, Motility and Chemotaxis". Helicobacter pylori: Molecular Genetics and Cellular Biology (Yamaoka Y, ed.). Caister Academic Press. ISBN   978-1-904455-31-8. .
10. Zakharova N.; Paster B. J.; Wesley I.; Dewhirst F. E.; Berg D. E.; Severinov K. V. (1999). "Fused and overlapping rpoB and rpoC genes in Helicobacters, Campylobacters, and related bacteria". J Bacteriol. 181 (12): 3857–3859. doi:10.1128/JB.181.12.3857-3859.1999. PMC   93870 . PMID   10368167.
11. Bento-Miranda M, Figueiredo C (December 2014). "Helicobacter heilmannii sensu lato: an overview of the infection in humans". World Journal of Gastroenterology. 20 (47): 17779–87. doi: 10.3748/wjg.v20.i47.17779 . PMC   4273128 . PMID   25548476.
12. Iwanczak B, Biernat M, Iwanczak F, Grabinska J, Matusiewicz K, Gosciniak G (April 2012). "The clinical aspects of Helicobacter heilmannii infection in children with dyspeptic symptoms". Journal of Physiology and Pharmacology. 63 (2): 133–6. PMID   22653899.
13. Ménard A, Smet A (September 2019). "Review: Other Helicobacter species". Helicobacter. 24 (Suppl 1): e12645. doi:10.1111/hel.12645. PMID   31486233.
14. Sayers; et al. "Helicobacter". National Center for Biotechnology Information (NCBI) taxonomy database. Retrieved 9 September 2023.
15. "The LTP" . Retrieved 10 December 2024.
16. "LTP_all tree in newick format" . Retrieved 10 December 2024.
17. "LTP_10_2024 Release Notes" (PDF). Retrieved 10 December 2024.
18. "GTDB release 09-RS220". Genome Taxonomy Database . Retrieved 10 May 2024.
19. "bac120_r220.sp_labels". Genome Taxonomy Database . Retrieved 10 May 2024.
20. "Taxon History". Genome Taxonomy Database . Retrieved 10 May 2024.

External links

• Helicobacter genomes and related information at PATRIC, a Bioinformatics Resource Center funded by NIAID
• List of species in Helicobacter, with links to sequence information
• Helicobacter at BacDive - the Bacterial Diversity Metadatabase