耐盐红螺菌拮抗物质的分离纯化及特性分析

耐盐红螺菌的无菌代谢产物经CM—Sephadex C-50弱阳离子交换色谱柱分离，获得3个蛋白吸收峰：PSB2-1’峰，PSB2—2’峰，PSB2—3’峰。其中PSB2-1’峰对病原菌具有拮抗作用。PSB2-1’峰组分样品经透析脱盐，后进行SDS—PAGE电泳检测，其冷冻干燥样品进行毛细管电泳与MALDI—TOF质谱鉴定，结果表明PSB2-1’峰的抑菌蛋白物质已达到较高纯度，其准确分子量为9290Da。耐盐红螺菌拮抗物质具有较好的热稳定性，对紫外线不敏感，但对酸碱性较敏感；用蛋白酶处理，其抑菌活性受枯草杆菌蛋白酶、胃蛋白酶和胰蛋白酶的影响。耐盐红螺菌产生的拮抗物质可初步归属于小分子热稳定肽(SHSP)。

Purification and characteristic analysis of antagonistic substances produced by salt-resistant Rhodospirillaceae bacteria

In order to characterize the property of metabolic substances of salt-resistant Rhodospirillaceae bacteria, the aseptic metabolic substances were purified by column chromatography on CM-Sephadex C-50. Three protein peaks: PSB2-1', PSB2-2', PSB2-3' were obtained. The protein peak of PSB2-1' had inhibiting activity against the pathogens. The antibacterial protein peak of PSB2-1' was confirmed as electrophoresis purity with SDS-PAGE. Only one band was shown when antibacterial protein was checked by capillary zone electrophoresis. And the molecular weight of antibacterial protein was 9290 Da checked by mass spectrometry. The antagonistic products produced by salt-resistant Rhodospirillaceae bacteria were heat-stable and were not sensitive to ultraviolet radiation, but sensitive to acidity and alkalinity. And the inhibitory activity was influenced by treatment with trypsin, pepsin and subtilisin. The antagonistic substances produced by salt-resistant Rhodospirillaceae bacteria could be preliminarily classified with small heat-stable peptide (SHSP).