Institute for Biochemistry, Albert-Ludwigs-Universität Freiburg, Albertstrasse 21, 79104, Freiburg, Germany.
Institute of Microbiology, University of Stuttgart, Allmandring 31, 70550, Stuttgart, Germany.
Sci Rep. 2017 Jul 21;7(1):6179. doi: 10.1038/s41598-017-05268-2.
Latex clearing proteins (Lcps) are rubber oxygenases that catalyse the extracellular cleavage of poly (cis-1,4-isoprene) by Gram-positive rubber degrading bacteria. Lcp of Streptomyces sp. K30 (Lcp) is a b-type cytochrome and acts as an endo-type dioxygenase producing C and higher oligo-isoprenoids that differ in the number of isoprene units but have the same terminal functions, CHO-CH- and -CH-COCH. Our analysis of the Lcp structure revealed a 3/3 globin fold with additional domains at the N- and C-termini and similarities to globin-coupled sensor proteins. The haem group of Lcp is ligated to the polypeptide by a proximal histidine (His198) and by a lysine residue (Lys167) as the distal axial ligand. The comparison of Lcp structures in a closed and in an open state as well as spectroscopic and biochemical analysis of wild type and Lcp muteins provided insights into the action of the enzyme during catalysis.
胶乳清除蛋白 (Lcps) 是橡胶加氧酶，可催化革兰氏阳性橡胶降解菌对聚（顺式-1,4-异戊二烯）的细胞外裂解。链霉菌属 K30 的 Lcp（Lcp）是一种 b 型细胞色素，作为一种内切型双加氧酶，产生 C 和更高的寡异戊二烯，它们在异戊二烯单元的数量上有所不同，但具有相同的末端功能，CHO-CH-和-CH-COCH。我们对 Lcp 结构的分析揭示了一个 3/3 球蛋白折叠，在 N 和 C 末端具有额外的结构域，并与球蛋白偶联传感器蛋白具有相似性。Lcp 的血红素基团通过近端组氨酸 (His198) 和赖氨酸残基 (Lys167) 与多肽连接，作为远端轴向配体。对闭合和开放状态下的 Lcp 结构的比较以及野生型和 Lcp 突变体的光谱和生化分析为酶在催化过程中的作用提供了深入了解。
