Johansson T, Nyman P O
Department of Biochemistry, Lund University, Sweden.
Gene. 1996 Apr 17;170(1):31-8. doi: 10.1016/0378-1119(95)00846-2.
A gene cluster from the white-rot basidiomycete Trametes (Coriolus) versicolor (Tv) PRL 572 containing three structural genes, LPGIII, LPGIV and MPGI, was characterized. The genes are arranged in the same transcriptional direction, within a 10-kb region, and found to encode quantitatively dominant isozymes of lignin peroxidase (LP) and manganese peroxidase (MP). The second gene in sequence, LPGIV, predicts a 346-amino-acid (aa) mature polypeptide (36.9 kDa, pI 4.31) which is identical with the partial aa sequence information available on the LP12 isozyme (43.1 kDa, pI 3.27). The first gene, LPGIII, encodes a 341-aa polypeptide (36.1 kDa, pI 3.93) which has not been identified at the protein level. However, the similarity of LPGIV would suggest that the predicted product is an LP-type enzyme. LPGIII and LPGIV are homologous to the tandemly arranged genes LPGII and LPGI, respectively, recently described by Jönsson and Nyman [Biochim. Biophys. Acta 1218 (1994) 408-412]. The homologous genes, LPGIII/LPGII and LPGIV/LPGI, are 99% and 96% identical in sequence, respectively, and are predicted to encode identical polypeptides, since base substitutions in the predicted exons are all synonymous. The third gene, MPGI, is different in intron-exon organization and predicted to be disrupted by five rather than six introns, as are the LP genes. The deduced polypeptide, 339 aa in size (35.9 kDa, pI 4.07), is identical with the partial aa sequence information available for isozyme MP2 (44.5 kDa, pI 3.09). The MPGI- and LPGIV-encoded polypeptides are 70% identical in sequence which suggests that MP and LP from Tv may be regarded as members of the same family within the plant peroxidase superfamily. Most importantly, this study identifies a gene encoding the MP2 isozyme, and further shows that genes encoding MP and LP can be closely linked on the chromosome and may be coordinately transcribed.
对来自白腐担子菌云芝（Trametes (Coriolus) versicolor，Tv）PRL 572的一个基因簇进行了表征，该基因簇包含三个结构基因LPGIII、LPGIV和MPGI。这些基因在10 kb的区域内按相同的转录方向排列，并且发现它们编码木质素过氧化物酶（LP）和锰过氧化物酶（MP）的数量上占主导的同工酶。序列中的第二个基因LPGIV预测编码一个346个氨基酸（aa）的成熟多肽（36.9 kDa，pI 4.31），它与LP12同工酶（43.1 kDa，pI 3.27）上可用的部分氨基酸序列信息相同。第一个基因LPGIII编码一个341个氨基酸的多肽（36.1 kDa，pI 3.93），在蛋白质水平上尚未被鉴定。然而，LPGIV的相似性表明预测产物是一种LP型酶。LPGIII和LPGIV分别与Jönsson和Nyman最近描述的串联排列的基因LPGII和LPGI同源[生物化学与生物物理学报1218 (1994) 408 - 412]。同源基因LPGIII/LPGII和LPGIV/LPGI的序列分别有99%和96%相同，并且由于预测外显子中的碱基替换都是同义的，所以预计编码相同的多肽。第三个基因MPGI在内含子 - 外显子组织上不同，预计被五个而非六个内含子打断，LP基因也是如此。推导的多肽大小为339个氨基酸（35.9 kDa，pI 4.07），与同工酶MP2（44.5 kDa，pI 3.09）上可用的部分氨基酸序列信息相同。MPGI和LPGIV编码的多肽在序列上有70%相同，这表明来自Tv的MP和LP可能被视为植物过氧化物酶超家族中同一家族的成员。最重要的是，这项研究鉴定了一个编码MP2同工酶的基因，并进一步表明编码MP和LP的基因在染色体上可能紧密相连并且可能协同转录。
