Smithson S L, Paterson I C, Bailey A M, Screen S E, Hunt B A, Cobb B D, Cooper R M, Charnley A K, Clarkson J M
Microbial Pathogenicity Group, School of Biology and Biochemistry, University of Bath, UK.
Gene. 1995 Dec 1;166(1):161-5. doi: 10.1016/0378-1119(95)00609-3.
Metarhizium anisophilae (Ma) secretes a range of proteases when grown in vitro on insect cuticle. A trypsin-like serine protease, PR2, was purified from culture filtrates by anion exchange chromatography and the N-terminal sequence determined. Using oligodeoxyribonucleotide probes based on this sequence and that of the highly conserved trypsin active site, a gene was isolated from a lambda EMBL3 genomic library of Ma isolate ME1. Sequencing of the gene and RT-PCR revealed that the gene contains two introns which are 94 and 40 bp long. The deduced protein consists of 254 amino acids, has a putative signal sequence to allow transport into the endoplasmic reticulum and probably undergoes a second proteolytic processing step at its N terminus to yield the mature enzyme. The putative mature enzyme has extensive homology with other serine proteases of the trypsin subclass and, in particular, with the trypsin characterised from Fusarium oxysporum.
当嗜绿僵菌（Ma）在昆虫表皮上进行体外培养时，它会分泌一系列蛋白酶。一种类胰蛋白酶丝氨酸蛋白酶PR2，通过阴离子交换色谱法从培养滤液中纯化出来，并测定了其N端序列。基于该序列以及高度保守的胰蛋白酶活性位点的序列，使用寡脱氧核糖核苷酸探针，从Ma分离株ME1的λEMBL3基因组文库中分离出一个基因。该基因的测序和逆转录聚合酶链反应（RT-PCR）表明，该基因包含两个长度分别为94和40 bp的内含子。推导的蛋白质由254个氨基酸组成，有一个假定的信号序列以便转运到内质网中，并且可能在其N端经历第二个蛋白水解加工步骤以产生成熟酶。假定的成熟酶与胰蛋白酶亚类的其他丝氨酸蛋白酶具有广泛的同源性，特别是与尖孢镰刀菌中鉴定的胰蛋白酶具有同源性。
