title: Chitin degradation and utilization by virulent Aeromonas hydrophila strain ML10-51K.
abstract: Virulent Aeromonas hydrophila (vAh) is one of the most important bacterial pathogens that causes persistent outbreaks of motile Aeromonas septicemia in warm-water fishes. The survivability of this pathogen in aquatic environments is of great concern. The aim of this study was to determine the capability of the vAh strain ML10-51K to degrade and utilize chitin. Genome-wide analysis revealed that ML10-51K encodes a suite of proteins for chitin metabolism. Assays in vitro showed that four chitinases, one chitobiase and one chitin-binding protein were secreted extracellularly and participated in chitin degradation. ML10-51K was shown to be able to use not only N-acetylglucosamine and colloidal chitin but also chitin flakes as sole carbon sources for growth. This study indicates that ML10-51K is a highly chitinolytic bacterium and suggests that the capability of effective chitin utilization could enable the bacterium to attain high densities when abundant chitin is available in aquatic niches.
authors.affiliation: Aquatic Animal Health Research Unit, USDA-ARS, 990 Wire Road, Auburn, AL, 36832, USA. Dunhua.zhang@ars.usda.gov.
authors.forename: Dunhua
authors.identifier: http://orcid.org/0000-0003-3773-0608
authors.initials: D
authors.lastname: Zhang
authors.affiliation: Aquatic Animal Health Research Unit, USDA-ARS, 990 Wire Road, Auburn, AL, 36832, USA.
authors.forename: De-Hai
authors.initials: DH
authors.lastname: Xu
authors.affiliation: College of Fisheries and Life Sciences, Shanghai Ocean University, Pudong New District, Shanghai, 201306, China.
authors.forename: Junqiang
authors.initials: J
authors.lastname: Qiu
authors.affiliation: Department of Biological Sciences, Auburn University, Auburn, AL, USA.
authors.forename: Cody R
authors.initials: CR
authors.lastname: Rasmussen-Ivey
authors.affiliation: Department of Biological Sciences, Auburn University, Auburn, AL, USA.
authors.forename: Mark R
authors.initials: MR
authors.lastname: Liles
authors.affiliation: Aquatic Animal Health Research Unit, USDA-ARS, 990 Wire Road, Auburn, AL, 36832, USA.
authors.forename: Benjamin H
authors.initials: BH
authors.lastname: Beck
mesh_terms: D000117:Acetylglucosamine / Q000378:metabolism; D016980:Aeromonas hydrophila / Q000201:enzymology* / Q000235:genetics / Q000472:pathogenicity; D000818:Animals; D002686:Chitin / Q000378:metabolism*; D002688:Chitinases / Q000378:metabolism
chemical_list: D002686:Chitin; D002688:Chitinases; D000117:Acetylglucosamine
keywords: Chitin degradation; Chitin utilization; Chitinase; Chitinolytic enzymes; Virulent Aeromonas hydrophila