title: Chondroitinase AC: A host-associated genetic feature of Helicobacter bizzozeronii.
abstract: Investigating mechanisms involved in host adaptation is crucial to understand pathogen evolution. Helicobacter species appear to have a host species-specific tropism, coevolving with their natural hosts, and to develop several strategies allowing the colonization of the stomach throughout lifetime of their hosts. However, little is known about genetic features associated with the adaptation to a specific animal host. In this study we discovered a polysaccharide lyase that is expressed by the canine-associated species H. bizzozeronii and acts as chondroitinase AC-type lyase of broad specificity. Except for its low pH-optimum between pH 4.0 and pH 5.5, the properties of the H. bizzozeronii chondroitin lyase AC resemble the ones from Arthrobacter aurescens. However, homologues of this gene have been detected only in Helicobacter species colonizing the canine and feline gastric mucosa. Since a unique feature of the canine stomach is the secretion of chondroitin-4-sulphate in the gastric juice of the fundus mucosa by chief cells, the expression of chondroitinase AC by H. bizzozeronii is likely the consequence of adaptation of this bacterium to its host and a potential link to gastric disorders in dogs.
authors.affiliation: Department of Medical Biochemistry and Microbiology (IMBIM), Uppsala University, BMC, Box 582, SE-751 23 Uppsala, Sweden. Electronic address: Ramesh.B.Namburi@imbim.uu.se.
authors.forename: Ramesh Babu
authors.initials: RB
authors.lastname: Namburi
authors.affiliation: INRA, ChemSyBio, UMR 1319 Micalis, F-78350 Jouy-en-Josas, France; AgroParisTech, ChemSyBio, UMR Micalis, F-78350 Jouy-en-Josas, France.
authors.forename: Olivier
authors.initials: O
authors.lastname: Berteau
authors.affiliation: Department of Medical Biochemistry and Microbiology (IMBIM), Uppsala University, BMC, Box 582, SE-751 23 Uppsala, Sweden.
authors.forename: Dorothe
authors.initials: D
authors.lastname: Spillmann
authors.affiliation: Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, P.O. Box 66, Agnes Sjöbergin katu 2, FI-00014 University of Helsinki, Finland. Electronic address: Mirko.Rossi@helsinki.fi.
authors.forename: Mirko
authors.initials: M
authors.lastname: Rossi
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics; D000818:Animals; D002415:Cats; D002809:Chondroitin Sulfates / Q000737:chemistry / Q000378:metabolism; D002810:Chondroitinases and Chondroitin Lyases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D004187:Disaccharides / Q000378:metabolism; D004283:Dog Diseases / Q000201:enzymology / Q000382:microbiology*; D004285:Dogs; D005753:Gastric Mucosa / Q000378:metabolism; D016998:Helicobacter / Q000201:enzymology* / Q000235:genetics*; D016481:Helicobacter Infections / Q000382:microbiology*; D006790:Host-Parasite Interactions / Q000235:genetics*; D006863:Hydrogen-Ion Concentration; D008958:Models, Molecular; D017434:Protein Structure, Tertiary; D017386:Sequence Homology, Amino Acid; D013379:Substrate Specificity
chemical_list: D004187:Disaccharides; D002809:Chondroitin Sulfates; D002810:Chondroitinases and Chondroitin Lyases
keywords: Canine gut microbiota; Carbohydrate lyases; Chondroitin sulphate; Glycosaminoglycan lyase; Helicobactor bizzozeronii