Sangkhobol and Skerman describe the isolation and characterization of five strains of a long, filamentous, gliding bacterium with distinctive properties. The organism produces myxospores through transformation of filaments into spherical bodies without forming fruiting bodies, characteristic of myxobacteria. Notably, it strongly hydrolyzes chitin but is non-cellulolytic, distinguishing it from related organisms. The strains were isolated from diverse environmental sources including pine litter and freshwater habitats across Australia. The authors propose a new genus, Chitinophaga, containing the single species Chitinophaga pinensis, with type strain UQM 2034. The organism measures 0.5–0.8 μm in diameter by approximately 40 μm in length during the gliding stage and produces yellow pigmentation. It exhibits oxidative and fermentative metabolism, produces urease, and is catalase-positive but oxidase-negative. The five strains show guanine-plus-cytosine DNA content ranging from 42.88 to 45.61 mol%, supporting their classification as a single species. The organism differs markedly from Sporocytophaga myxococcoides and Lysobacter species in morphology, substrate utilization, and DNA composition, justifying establishment as a distinct genus.

Key findings

• A new myxobacterial genus Chitinophaga is proposed, containing the species C. pinensis, isolated from five environmental samples in Australia
• C. pinensis strongly hydrolyzes chitin but cannot hydrolyze cellulose, starch, alginate, or agar, distinguishing it from related gliding bacteria
• The organism produces myxospores (0.8–0.9 μm diameter) without fruiting body formation and exhibits variable germination patterns
• DNA G+C content ranges from 42.88 to 45.61 mol%, approximately 9% different from S. myxococcoides and ~20% different from Lysobacter species
• C. pinensis is susceptible to tetracycline, streptomycin, and chloramphenicol but resistant to neomycin, kanamycin, penicillin G, and erythromycin