PDF(Pubmed)
Abstract：
The discovery of lytic polysaccharide monooxygenases (LPMOs), a family of copper-dependent enzymes that play a major role in polysaccharide degradation, has revealed the importance of oxidoreductases in the biological utilization of biomass. In fungi, a range of redox proteins have been implicated as working in harness with LPMOs to bring about polysaccharide oxidation. In bacteria, less is known about the interplay between redox proteins and LPMOs, or how the interaction between the two contributes to polysaccharide degradation. We therefore set out to characterize two previously unstudied proteins from the shipworm symbiont Teredinibacter turnerae that were initially identified by the presence of carbohydrate binding domains appended to uncharacterized domains with probable redox functions. Here, X-ray crystal structures of several domains from these proteins are presented together with initial efforts to characterize their functions. The analysis suggests that the target proteins are unlikely to function as LPMO electron donors, raising new questions as to the potential redox functions that these large extracellular multi-haem-containing c-type cytochromes may perform in these bacteria.
摘要：
裂解多糖单加氧酶（LPMO）的发现，在多糖降解中起主要作用的铜依赖性酶家族，揭示了氧化还原酶在生物质生物利用中的重要性。在真菌中，一系列氧化还原蛋白已被认为与LPMO一起工作以引起多糖氧化。在细菌中，对氧化还原蛋白和LPMO之间的相互作用知之甚少，或两者之间的相互作用如何促进多糖降解。因此，我们着手表征来自舰虫共生体Turedinibacterturnerae的两种先前未研究的蛋白质，这些蛋白质最初是通过将碳水化合物结合域附加到具有可能的氧化还原功能的未表征域上来鉴定的。这里,来自这些蛋白质的几个结构域的X射线晶体结构与表征其功能的初步努力一起呈现。分析表明，靶蛋白不太可能充当LPMO电子供体，提出了新的问题，潜在的氧化还原功能，这些大的细胞外多含血红素的c型细胞色素可能在这些细菌中执行。
