一株耐辐射考克氏菌的分离与鉴定

ISOLATION AND IDENTIFICATION OF AN IRRADIATION-RESISTANT BACTERIUM STRAIN OF Kocuria

从10kGy60Coγ射线辐照处理的新疆戈壁土壤中分离到一株耐辐射微生物I-7R,该菌菌落为橙红色革兰氏阳性球菌。最适生长温度为30℃,(G+C)mol%含量为67.5%,不具有氨苄青霉素、氯霉素、四环素、卡那霉素、潮霉素、利福平及壮观霉素等抗性。UV辐射生存曲线显示,I-7R菌株与大肠杆菌K-12相比,具有较强的紫外辐射抗性。16S rDNA序列比较分析表明I-7R菌株与Kocuria rosea、K.erythromyxa以及K.polaris同源性达到99%。结合I-7R菌株生理生化试验结果,该株菌归属于考克氏菌属(Kocuria),并与Kocuria rosea最为相近,暂命名为K.rosea I-7R。

An Gram-positive irradiation-resistant bacterium strain I-7R was isolated from an irradiated by（10 kGy） soil sample of the Gobi in Xinjiang Autonomous Region.The strain has the following characteristics：colonies was orangered,optimum growth temperature was 30℃ ,the（G ＋ C） mol% content of DNA was 67.5 % .The strain I-7R was sensitive to Amp,Km,Rif,Cm,Hyg,Tc and Aad.The UV survival curve showed that this strain had strong UVresistance compared with E.coli.K-12.The 16S rDNA of the I-7R strain shared highly similarity（99 % ） to K.rosea,K.erythromyxa and K.polaris.The strain I-7R belonged to Kocuria and was very close to K.rosea based on the 16S rDNA sequence analysis and the physiology and biochemical characteristics.It was proposed that the strain was designated as Kocuria rosea I-7R.