Department of Biology (Area 10), University of York, York, UK.
FEMS Microbiol Lett. 2012 Nov;336(2):131-8. doi: 10.1111/j.1574-6968.2012.02663.x. Epub 2012 Sep 13.
The ability to use the sialic acid, N-acetylneuraminic acid, Neu5Ac, as a nutrient has been characterized in a number of bacteria, most of which are human pathogens that encounter this molecule because of its presence on mucosal surfaces. The soil bacterium Corynebacterium glutamicum also has a full complement of genes for sialic acid catabolism, and we demonstrate that it can use Neu5Ac as a sole source of carbon and energy and isolate mutants with a much reduced growth lag on Neu5Ac. Disruption of the cg2937 gene, encoding a component of a predicted sialic acid-specific ABC transporter, results in a complete loss of growth of C. glutamicum on Neu5Ac and also a complete loss of [(14)C]-Neu5Ac uptake into cells. Uptake of [(14)C]-Neu5Ac is induced by pregrowth on Neu5Ac, but the additional presence of glucose prevents this induction. The demonstration that a member of the Actinobacteria can transport and catabolize Neu5Ac efficiently suggests that sialic acid metabolism has a physiological role in the soil environment.
许多细菌具有利用唾液酸（N-乙酰神经氨酸，Neu5Ac）作为营养物质的能力，这些细菌大多数都是人类病原体，因为它们存在于黏膜表面，所以会遇到这种分子。土壤细菌谷氨酸棒杆菌也拥有完整的唾液酸分解代谢基因，我们证明它可以将 Neu5Ac 作为唯一的碳源和能源利用，并分离到在 Neu5Ac 上生长滞后明显减少的突变体。破坏 cg2937 基因（编码一种预测的唾液酸特异性 ABC 转运蛋白的成分）会导致谷氨酸棒杆菌完全无法在 Neu5Ac 上生长，并且细胞对 [(14)C]-Neu5Ac 的摄取也完全丧失。[(14)C]-Neu5Ac 的摄取可通过在 Neu5Ac 上预生长诱导，但额外存在葡萄糖会阻止这种诱导。证明放线菌的成员能够有效地运输和分解 Neu5Ac，这表明唾液酸代谢在土壤环境中具有生理作用。
