Extracellular Polysaccharide-Degrading Proteome of Butyrivibrio proteoclasticus
Extracellular Polysaccharide-Degrading Proteome of Butyrivibrio proteoclasticus
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DOI：
10.1021/pr200864j
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发表时间：
2012-01-01
影响因子：
4.4
通讯作者：
Jordan, T. William
中科院分区：
文献类型：
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作者：
Dunne, Jonathan C.;Li, Dong;Jordan, T. William
植物多糖降解瘤胃微生物是反刍动物健康和生产力的基础。proteoclasticus Butyrivibrio B316(T)是一种革兰氏阳性的产生丁酸盐的厌氧细菌，在瘤胃半纤维素降解中起关键作用。以凝胶为基础的蛋白质组学用于检测以木聚糖或木糖作为唯一补充碳源体外培养的细胞中分泌蛋白的生长阶段依赖丰度模式。鉴定出的30种分泌蛋白中有5种多糖酶和2种碳水化合物结合蛋白（CBPs）。内切-1,4- β -木聚糖酶Xyn10B在木聚糖培养细胞的培养基中含量高出17.5倍，表明其在半纤维素降解中起重要作用。三种非木聚糖水解酶和两种CBPs的分泌表明它们通过水解或破坏相关结构多糖来增强半纤维素降解。鉴定了16种atp结合盒（ABC）转运体底物结合蛋白，其中一些蛋白在生长条件下的相对丰度水平发生了变化，这表明它们对低聚糖的摄取很重要。本研究表明，B. proteoclasticus调节半纤维素降解酶和atp依赖性糖摄取系统的分泌，以响应生长底物，并支持该生物在瘤胃中对多糖降解做出重要贡献的观点。
Plant polysaccharide-degrading rumen microbes are fundamental to the health and productivity of ruminant animals. Butyrivibrio proteoclasticus B316(T) is a Gram-positive, butyrate-producing anaerobic bacterium with a key role in hemicellulose degradation in the rumen. Gel-based proteomics was used to examine the growth-phase-dependent abundance patterns of secreted proteins recovered from cells grown in vitro with xylan or xylose provided as the sole supplementary carbon source. Five polysaccharidases and two carbohydrate-binding proteins (CBPs) were among 30 identified secreted proteins. The endo-1,4-beta-xylanase Xyn10B was 17.5-fold more abundant in the culture medium of xylan-grown cells, which suggests it plays an important role in hemicellulose degradation. The secretion of three nonxylanolytic enzymes and two CBPs implies they augment hemicellulose degradation by hydrolysis or disruption of associated structural polysaccharides. Sixteen ATP-binding cassette (ABC) transporter substrate-binding proteins were identified, several of which had altered relative abundance levels between growth conditions, which suggests they are important for oligosaccharide uptake. This study demonstrates that B. proteoclasticus modulates the secretion of hemicellulose-degrading enzymes and ATP-dependent sugar uptake systems in response to growth substrate and supports the notion that this organism makes an important contribution to polysaccharide degradation in the rumen.