Isolation and identification of a pathogen of silkworm Bombyx mori.
A pathogenic bacterial strain, ST-1, was isolated from a naturally infected silkworm. The strain was identified on the basis of its physiological and biochemical properties and the results of sequence analysis of its 16S rRNA gene. The results of the 16S rRNA gene sequence analysis revealed that ST-1 shared the highest sequence identity (more than 99%) with Pseudomonas chlororaphis subsp. aurantiaca. ST-1 bacteria were gram-negative and 0.7-0.9 × 1.3-1.5 μm long, short rods with rounded ends. The strain could utilize sodium citrate, malonate, D-glucose, sucrose, D-fructose, D-mannose, and L-arabinose. Pathogenicity of ST-1 for silkworm could be depicted as a linear regression of the logarithm (y) of ST-1 concentration against probability (x) (y = 0.4040 + 0.0600x). The median lethal concentration (LC(50)) was 2.12 × 10(4) cfu/ml. In conclusion, ST-1 was identified as Ps. chlororaphis subsp. aurantiaca. This is the first report that Ps. aurantiaca is a pathogen for silkworm Bombyx mori.
College of Biotechnology and Environmental Engineering, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu Province, 212018, China.
Heng-Ping
HP
Tao
Zhong-Yuan
ZY
Shen
Feng
F
Zhu
Xiao-Fang
XF
Xu
Xu-Dong
XD
Tang
Li
L
Xu
D000818:Animals; D015373:Bacterial Typing Techniques; D012831:Bombyx / Q000382:microbiology*; D050260:Carbohydrate Metabolism; D016000:Cluster Analysis; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D008969:Molecular Sequence Data; D010802:Phylogeny; D011549:Pseudomonas / Q000145:classification / Q000302:isolation & purification* / Q000378:metabolism / Q000472:pathogenicity*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D016019:Survival Analysis
D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S