Erysipelothrix larvae sp. nov., isolated from the larval gut of the rhinoceros beetle, Trypoxylus dichotomus (Coleoptera: Scarabaeidae)

Abstract

A nov.l, Gram-stain positive, facultative anaerobic, non-motile and straight to curve rod shaped bacterium, strain LV19T was isolated from the larval gut of the rhinoceros beetle, Trypoxylus dichotomus, which was collected from Yeong-dong, Chuncheongbuk-do, South Korea. The colonies of the new isolate were convex, circular, cream white in color and 1-2 mm in diameter after 3 days incubation on Tryptic Soy Agar at 37 °C. Based on the 16S rRNA gene sequence similarity, the new isolate was most closely related to Erysipelothrix inopinata MF-EP02T, E. rhusiopathiae ATCC 19414 T and E. tonsillarum T-305T (94.8, 93.8 and 93.7 % similarity, respectively). Strain LV19T grew optimally at 37 °C, at pH 8.0 and in the presence of 0.5 % (w/v) NaCl. Oxidase activity and catalase activity were negative. The major cellular fatty acids (>10 %) were C18:2 cis-9,12 (28.9 %), C18:1 cis-9 (22.3 %), C16:0 (22.2 %) and C18:0 (18.5 %). The cell-wall hydrolysates contained ribose as a major sugar. Major polar lipids were phosphatidylglycerol and three unidentified glycolipids. No quinone was detected. The G+C content of the genomic DNA was 36.3 mol%. The levels of DNA-DNA relatedness between strain LV19T and all the reference strains were less than 20 %. On the basis of polyphasic evidence from this study, the isolate is considered to represent a nov.l sp.cies of the genus Erysipelothrix, for which the name Erysipelothrix larvae sp. nov. is proposed; the type strain is LV19T (=KCTC 33523T = DSM 28480T).