Ohman D E, Cryz S J, Iglewski B H
J Bacteriol. 1980 Jun;142(3):836-42. doi: 10.1128/jb.142.3.836-842.1980.
Pseudomonas aeruginosa PAO mutants defective in elastase were isolated by plate assays of nitrosoguanidine-mutagenized clones. A total of 75 elastase mutants were isolated from 43,000 mutagenized clones. One mutant (PAO-E64) was apparently identical to the parental strain except for its deficiency in elastase activity. This mutant produced an enzyme which was antigenically indistinguishable from parental elastase. Furthermore, equal levels of elastase antigen were produced by this mutant and its parental strain. The mutant elastase, however, had greatly reduced enzymatic activity. Mutant PAO-E64 is presumed to have a mutation in the structural gene for elastase. We have designated the genotype of the mutation in PAO-E64 as lasA1.
通过对经亚硝基胍诱变的克隆进行平板测定，分离出了铜绿假单胞菌PAO中弹性蛋白酶缺陷型突变体。从43,000个诱变克隆中总共分离出75个弹性蛋白酶突变体。一个突变体（PAO-E64）除了弹性蛋白酶活性缺陷外，显然与亲本菌株相同。该突变体产生的一种酶在抗原性上与亲本弹性蛋白酶无法区分。此外，该突变体及其亲本菌株产生的弹性蛋白酶抗原水平相等。然而，突变体弹性蛋白酶的酶活性大大降低。推测突变体PAO-E64的弹性蛋白酶结构基因发生了突变。我们将PAO-E64中的突变基因型指定为lasA1。
