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核心技术专利：CN118964589B侵权必究

核心技术专利：CN118964589B侵权必究

Biochem J. 1971 Jul;123(4):493-500. doi: 10.1042/bj1230493.

The beta-lactamase specified by the R-1818 resistance factor in Escherichia coli was purified 300-fold; the resulting preparation gave a single peak on Sephadex G-100 and a single band on polyacrylamide-gel electrophoresis. 2. The beta-lactamase specified by the same R-factor in Proteus mirabilis was purified over 2000-fold, but was still far from pure. The specific activity of this preparation was one-fifth that of the purified enzyme from E. coli. 3. The two enzymes were shown to be identical as regards substrate specificity, pH optimum, K(m) values and molecular weight. 4. It is suggested that the low beta-lactamase activity of extracts of P. mirabilis (R-1818), about 5% of that from E. coli (R-1818) in crude extracts, could be due to inefficient transcription of the R-factor DNA by Proteus RNA polymerase.

对大肠杆菌中由R - 1818抗性因子所产生的β - 内酰胺酶进行了300倍的纯化；最终制剂在葡聚糖G - 100上呈现单一峰，在聚丙烯酰胺凝胶电泳上呈现单一带。2. 奇异变形杆菌中由相同R因子所产生的β - 内酰胺酶被纯化了2000多倍，但仍远未达到纯品。该制剂的比活性是来自大肠杆菌的纯化酶的五分之一。3. 就底物特异性、最适pH值、米氏常数（K(m)）值和分子量而言，这两种酶被证明是相同的。4. 有人提出，奇异变形杆菌（R - 1818）提取物中低水平的β - 内酰胺酶活性，在粗提物中约为大肠杆菌（R - 1818）的5%，可能是由于变形杆菌RNA聚合酶对R因子DNA的转录效率低下所致。

Biochem J. 1971 Jul;123(4):493-500. doi: 10.1042/bj1230493.

The beta-lactamase specified by the R-1818 resistance factor in Escherichia coli was purified 300-fold; the resulting preparation gave a single peak on Sephadex G-100 and a single band on polyacrylamide-gel electrophoresis. 2. The beta-lactamase specified by the same R-factor in Proteus mirabilis was purified over 2000-fold, but was still far from pure. The specific activity of this preparation was one-fifth that of the purified enzyme from E. coli. 3. The two enzymes were shown to be identical as regards substrate specificity, pH optimum, K(m) values and molecular weight. 4. It is suggested that the low beta-lactamase activity of extracts of P. mirabilis (R-1818), about 5% of that from E. coli (R-1818) in crude extracts, could be due to inefficient transcription of the R-factor DNA by Proteus RNA polymerase.

对大肠杆菌中由R - 1818抗性因子所产生的β - 内酰胺酶进行了300倍的纯化；最终制剂在葡聚糖G - 100上呈现单一峰，在聚丙烯酰胺凝胶电泳上呈现单一带。2. 奇异变形杆菌中由相同R因子所产生的β - 内酰胺酶被纯化了2000多倍，但仍远未达到纯品。该制剂的比活性是来自大肠杆菌的纯化酶的五分之一。3. 就底物特异性、最适pH值、米氏常数（K(m)）值和分子量而言，这两种酶被证明是相同的。4. 有人提出，奇异变形杆菌（R - 1818）提取物中低水平的β - 内酰胺酶活性，在粗提物中约为大肠杆菌（R - 1818）的5%，可能是由于变形杆菌RNA聚合酶对R因子DNA的转录效率低下所致。