Zámocký Marcel, Furtmüller Paul G, Obinger Christian
Metalloprotein Research Group, Division of Biochemistry, Department of Chemistry, BOKU, University of Natural Resources and Applied Life Sciences, Muthgasse 18, A-1190 Vienna Austria.
Biochem Soc Trans. 2009 Aug;37(Pt 4):772-7. doi: 10.1042/BST0370772.
Catalase/peroxidases (KatGs) are bifunctional haem b-containing (Class I) peroxidases with overwhelming catalase activity and substantial peroxidase activity with various one-electron donors. These unique oxidoreductases evolved in ancestral bacteria revealing a complex gene-duplicated structure. Besides being found in numerous bacteria of all phyla, katG genes were also detected in genomes of lower eukaryotes, most prominently of sac and club fungi. Phylogenetic analysis demonstrates the occurrence of two distinct groups of fungal KatGs that differ in localization, structural and functional properties. Analysis of lateral gene transfer of bacterial katGs into fungal genomes reveals that the most probable progenitor was a katG from a bacteroidetes predecessor. The putative physiological role(s) of both fungal KatG groups is discussed with respect to known structure-function relationships in bacterial KatGs and is related with the acquisition of (phyto)pathogenicity in fungi.
过氧化氢酶/过氧化物酶（KatGs）是含血红素b的双功能（I类）过氧化物酶，具有极强的过氧化氢酶活性以及与各种单电子供体相关的显著过氧化物酶活性。这些独特的氧化还原酶在古老细菌中进化而来，呈现出复杂的基因重复结构。除了在所有门类的众多细菌中被发现外，katG基因还在低等真核生物的基因组中被检测到，最显著的是子囊菌和担子菌。系统发育分析表明，真菌KatGs存在两个不同的组，它们在定位、结构和功能特性上有所不同。对细菌katGs向真菌基因组的横向基因转移分析表明，最可能的祖先基因是来自拟杆菌前身的katG。本文结合细菌KatGs中已知的结构-功能关系，讨论了这两类真菌KatG的假定生理作用，并将其与真菌（植物）致病性的获得联系起来。
