Chitinilyticum litopenaei sp nov., isolated from a freshwater shrimp pond, and emended description of the genus Chitinilyticum

Strain C1(T), originally isolated from surface water of a freshwater pond located in Pingtung (southern Taiwan) used for culture of Pacific white shrimp (Litopenaeus vannamei), was subjected to a polyphasic taxonomic analysis. The strain exhibited strong chitinolytic; activity and was able to grow under aerobic and anaerobic conditions by utilizing chitin exclusively as the carbon, nitrogen and energy source. Phylogenetic analysis of the 16S rRNA gene sequence revealed a clear affiliation to the Betaproteobacteria, with the closest relatives being Chitinilyticum aquatile C14(T) and Chitinibacter tainanensis S1(T), respectively showing 96.7 and 93.6% 16S rRNA gene sequence similarity. The predominant fatty acids detected in cells of strain c1(T) were C-16:0, C-18:1 omega 7c and summed feature 3 (C-16:1 omega 7c and/or iso-C-15:0 2-OH). The G+C content of the genomic DNA was 62.2 +/- 1.0 mol%. On the basis of phylogenetic analysis, DNA-DNA hybridization data, physiological and biochemical characteristics and fatty acid compositions, the organism was shown to belong to the genus Chitinilyticum whilst representing a novel species within this genus, for which we propose the name Chitinilyticum litopenaei sp. nov. (type strain c1(T) =DSM 21440(T) =BCRC 17609(T)).