Comparative Phenotype and Genome Analysis of Cellvibrio sp. PR1, a Xylanolytic and Agarolytic Bacterium from the Pearl River

Cellvibrio sp. PR1 is a xylanolytic and agarolytic bacterium isolated from the Pearl River. Strain PR1 is closely related to Cellvibrio fibrivorans and C. ostraviensis (identity > 98%). The xylanase and agarase contents of strain PR1 reach up to 15.4 and 25.9 U/mL, respectively. The major cellular fatty acids consisted of C16:0 (36.7%), C18:0 (8.8%), C20:0 (6.8%), C15:0 iso 2-OH or/and C16:1ω7c (17.4%), and C18:1ω7c or/and C18:1ω6c (6.7%). A total of 251 CAZyme modules (63 CBMs, 20 CEs, 128 GHs, 38 GTs, and 2 PLs) were identified from 3,730 predicted proteins. Genomic analysis suggested that strain PR1 has a complete xylan-hydrolyzing (5 β-xylanases, 16 β-xylosidases, 17 α-arabinofuranosidases, 9 acetyl xylan esterases, 4 α-glucuronidases, and 2 ferulic acid esterases) and agar-hydrolyzing enzyme system (2 β-agarases and 2 α-neoagarooligosaccharide hydrolases). In addition, the main metabolic pathways of xylose, arabinose, and galactose are established in the genome-wide analysis. This study shows that strain PR1 contains a large number of glycoside hydrolases.