PDF(Pubmed)
Abstract：
As a potent, pleiotropic regulatory protein in Gram-positive bacteria, catabolite control protein A (CcpA) mediates the transcriptional control of carbohydrate metabolism in Streptococcus bovis, a lactate-producing bacterium that plays an essential role in rumen acidosis in dairy cows. Although the rumen uptake of carbohydrates is multi-substrate, the focus of S. bovis research thus far has been on the glucose. With the aid of gene deletion, whole-genome sequencing, and transcriptomics, we have unraveled the role of CcpA in carbohydrate metabolism, on the one hand, and acidosis, on the other, and we show that the S. bovis strain S1 encodes \"Carbohydrate-Active Enzymes\" and that ccpA deletion slows the organism\'s growth rate and modulates the organic acid fermentation pathways toward lower lactate, higher formate, and acetate in the maltose and cellobiose. Furthermore, this study revealed the different regulatory functions of the CcpA protein in rumen metabolism and acidosis.IMPORTANCEThis study is important as it illustrates the varying regulatory role of the Streptococcus bovis catabolite control protein A protein in carbohydrate metabolism and the onset of acidosis in dairy cattle.
摘要：
作为一种强权，革兰氏阳性细菌中的多效性调节蛋白，代谢产物控制蛋白A（CcpA）介导牛链球菌碳水化合物代谢的转录控制，一种产乳酸的细菌，在奶牛瘤胃酸中毒中起重要作用。虽然碳水化合物的瘤胃摄取是多底物的，到目前为止，牛链球菌研究的重点一直是葡萄糖。借助基因缺失，全基因组测序，和转录组学，我们已经揭示了CpA在碳水化合物代谢中的作用，一方面,和酸中毒,另一方面,我们显示牛链球菌菌株S1编码“碳水化合物活性酶”，并且ccpA缺失减慢了生物体的生长速率并调节了有机酸发酵途径，使乳酸降低，高级甲酸盐，麦芽糖和纤维二糖中的乙酸盐。此外，这项研究揭示了CpA蛋白在瘤胃代谢和酸中毒中的不同调节功能。重要性这项研究很重要，因为它说明了牛链球菌分解代谢物控制蛋白A蛋白在碳水化合物代谢和奶牛酸中毒发作中的不同调节作用。
