Phenotyping and molecular characterization of Lysinibacillus sp. P-011 (GU288531) and their role in the development of Drosophila melanogaster

Abstract

The bacterial strain Lysinibacillus sp. (P-011) was isolated from the midgut of the Drosophila melanogaster larvae. The bacteria were gram positive, spore forming, rod shaped ranging from 1.86 to 2.5µm in length and 0.50 to 0.67 µm in diameter, positive for catalase, indole, oxidase, nitrate reduction, starch and gelatin hydrolysis, sensitive to tetracycline, chloramphenicol, doxycycline hydrochloride, gatifloxacin, ofloxacin, vancomycin, rifampicin, levofloxacin, ciprofloxacin, nalidixic acid, but resistant to ampicillin, streptomycin, gentamycin and kanamycin. The phylogenetic tree showed that the strain Lysinibacillus sp. P-011 (GU288531) branched with Lysinibacillus boronitolerans with 89% bootstrap support. Lysinibacillus sp. P-011 (~10⁵ cfu/ml) played an important role on larval development of D. melanogaster under controlled environmental condition. Wild larvae when fed on normal food as well as normal food mixed with ineffective antibiotics, developed puparium within seven days whereas took more than 10 days when fed on normal food mixed with anti P-011 antibiotics and sterile food mixed with bacterial suspension and anti P-011 antibiotics. 94 to 98% cured larvae developed puparium within seven days when fed on only sterile food mixed with bacterial suspension (P-011) or sterile food mixed with bacterial suspension (P-011) and ineffective antibiotics.

Key words: Drosophila melanogaster, gut-bacteria, larval development, Lysinibacillus sp. P-011 (GU288531), 16S rRNA gene sequence, phylogenetic tree.