原桃胶中1株芽孢杆菌的分离鉴定及其主要抗菌物质

从天然原桃胶分离到1 株产抑菌活性物质的芽孢杆菌TJ12。其发酵产物对金黄色葡萄球菌（Staphylococcusaureus）、藤黄微球菌（Micrococcus luteus）、蜡样芽孢杆菌（Bacillus cereus）和串珠镰刀菌（Fusarium moniliforme）有抑菌活性。结合菌落形态、生理生化指标、16S rRNA序列和gyrB序列将TJ12菌株鉴定为地衣芽孢杆菌（Bacillus licheniformis）。通过硫铵沉淀、有机溶剂萃取、羟丙基葡聚糖凝胶、高效液相色谱分离纯化，得到其主要活性物质。该物质对pH值、温度和3 种蛋白酶（胰蛋白酶、蛋白酶K、胃蛋白酶）有较好的稳定性。经电喷雾电离质谱分析，初步鉴定该株地衣芽孢杆菌TJ12的主要抗菌物质为杆菌肽A。

Isolation and Identification of a Bacillus from Peach Tree Gum and Its Main Antimicrobial Substance

A strain of Bacillus named as TJ12 was isolated from peach tree gum, which could produce antibacterial
substances. Its fermentation products had antibacterial activity against Staphylococcus aureus, Micrococcus luteus, Bacillus
cereus and Fusarium moniliforme. Through colony morphology, physiological and biochemical characterization and 16S
rRNA and gyrB sequence analysis, the strain was identified as Bacillus licheniformis. The major bioactive substance was
separated from its fermentation supernatant and purified by ammonium sulfate precipitation, organic solvent extraction,
Sephadex LH-20 column chromatography and high performance liquid chromatography. The major bioactive substance had
strong resistance to pH, temperature, and three proteases (trypsin, proteinase K, and pepsin). By electrospray ionization-mass
spectrometry analysis, we preliminarily identified this substance as bacitracin A.