Conservation of the chitin utilization pathway in the Vibrionaceae.
Vibrionaceae are regarded as important marine chitin degraders, and attachment to chitin regulates important biological functions; yet, the degree of chitin pathway conservation in Vibrionaceae is unknown. Here, a core chitin degradation pathway is proposed based on comparison of 19 Vibrio and Photobacterium genomes with a detailed metabolic map assembled for V. cholerae from published biochemical, genomic, and transcriptomic results. Further, to assess whether chitin degradation is a conserved property of Vibrionaceae, a set of 54 strains from 32 taxa were tested for the ability to grow on various forms of chitin. All strains grew on N-acetylglucosamine (GlcNAc), the monomer of chitin. The majority of isolates grew on alpha (crab shell) and beta (squid pen) chitin and contained chitinase A (chiA) genes. chiA sequencing and phylogenetic analysis suggest that this gene is a good indicator of chitin metabolism but appears subject to horizontal gene transfer and duplication. Overall, chitin metabolism appears to be a core function of Vibrionaceae, but individual pathway components exhibit dynamic evolutionary histories.
Hunt
Dana E
DE
Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, 48-417, 77 Massachusetts Avenue, Cambridge, MA 02139, USA.
Gevers
Dirk
D
Vahora
Nisha M
NM
Polz
Martin F
MF
D000117:Acetylglucosamine / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics; D002686:Chitin / Q000378:metabolism*; D002688:Chitinases / Q000235:genetics; D017124:Conserved Sequence; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D053858:Metabolic Networks and Pathways / Q000235:genetics*; D008969:Molecular Sequence Data; D010802:Phylogeny; D017422:Sequence Analysis, DNA; D014737:Vibrionaceae / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism*
D001426:Bacterial Proteins; D004269:DNA, Bacterial; D002686:Chitin; D002688:Chitinases; D000117:Acetylglucosamine