The extracellular emulsifier of Arthrobacter RAG-1 was deproteinized by hot phenol treatment and purified by fractional precipitation with (NH4)2SO4. The active fraction, precipitating between 30 and 35% saturation [EF-RAG(UET) WA], appeared to be homogeneous by immunodiffusion and sedimentation analysis. EF-RAG(UET) WA had an intrinsic viscosity of 750 cm3/g, a sedimentation constant of 6.06S, a diffusion constant of 5.25 × 10−8 cm2 s−1, and a partial molar volume of 0.712 cm3 g−1. From these data a weight average molecular weight of 9.76 × 105 and a viscosity average molecular weight of 9.88 × 105 were calculated. EF-RAG(UET)WA contained 46.7% C, 7.01% H, and 6.06% N. Titration of the nonreducing polymer gave a single inflection point (pK′ = 3.05), corresponding to 1.5 μmol of carboxyl groups per mg. Direct estimation of O-ester and hexose content of the highly acidic polymer yielded 0.65 and 0.29 μmol/mg, respectively. Mild alkaline hydrolysis released fatty acids with an average molecular weight of about 231. Strong acid hydrolysis of EF-RAG(UET)WA yielded d-glucose (minor), d-galactosamine (major), and an unidentified amino uronic acid (major).
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机译:通过热酚处理将节杆菌RAG-1的细胞外乳化剂脱蛋白,并通过用(NH4)2SO4分步沉淀进行纯化。沉淀在30%至35%饱和度之间的活性部分[EF-RAG(UET)WA]通过免疫扩散和沉降分析显示是均匀的。 EF-RAG(UET)WA的特性粘度为750 cm 3 sup> / g,沉降常数为6.06S,扩散常数为5.25×10 -8 sup> cm < sup> 2 sup> s -1 sup>,部分摩尔体积为0.712 cm 3 sup> g -1 sup>。从这些数据计算出重均分子量为9.76×10 5 sup>和粘均分子量为9.88×10 5 sup>。 EF-RAG(UET)WA含有46.7%的C,7.01%的H和6.06%的N。滴定非还原性聚合物可得到一个拐点(pK'= 3.05),相当于每毫克1.5μmol羧基。直接估算高酸性聚合物的O酯和己糖含量分别为0.65和0.29μmol/ mg。轻度碱水解会释放出平均分子量约为231的脂肪酸。EF-RAG(UET)WA的强酸水解会产生d-葡萄糖(次要),d-半乳糖胺(主要)和未鉴定的氨基糖醛酸(主要)。 。
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