Extracellular-nucleotide metabolisms of oral microorganisms

据报道，各种细菌栖息在口腔中，其中一些细菌可能导致其他区域的多种疾病。特别是血链球菌在心内膜炎的炎症部分和各种脓肿区域中被检测到。在这项研究中，我们研究了口腔链球菌是否代谢细胞外核苷酸，这是应该存在于脓肿区域。结果证实，血链球菌、戈登链球菌和唾液链球菌代谢CMP并产生氨和无机磷酸盐。因此，我们详细研究了这两种链球菌群的代谢差异。两个细菌组的无细胞提取物中的胞苷脱氨酶活性的显着程度。虽然S. sanguinis、血吸虫S. gordonii和S.唾液链球菌含有膜结合的5 '-核苷酸酶活性，但变形链球菌不含该活性。在无细胞提取物中，5 '-核苷酸酶活性较低。氧气闪光导致血细胞明显减少可产生某种活性氧并使5 '-核苷酸酶水解。血链球菌能分解AMP、GMP、UMP、deoxy AMP、deoxy CMP、deoxy GMP，产生无机磷。证实了S. sanguinis细胞从（deoxy-）AMP、（deoxy-）CMP产生氨。本研究发现S. sanguinis，S. gordonii和S.唾液肌能代谢细胞外5 ′-脱氧核苷酸。人们认为，这些事实对于了解身体各个区域以及牙菌斑中细菌的生态系统非常重要。

It has been reported that various bacteria inhabit in an oral cavity and some of these bacteria may cause several diseases in the other area. Especially Streptococcus sanguinis has been detected in the inflammation part of endocarditis and in various abscess regions. In this study we examined whether oral streptococci metabolize extra-cellular nucleotide which is supposed to exist in abscess regions. As a result, it was confirmed that Streptococcus sanguinis, Streptococcus gordonii and Streptococcus salivarius metabolized CMP and produced the ammonia and inorganic phosphate. Therefore, we examined the metabolic difference both these two streptococcal groups in detail. Both bacteria group had significant degree of cytidine deaminase activity in the cell-free extracts. Although S. sanguinis, S. gordonii and S. salivarius contained membrane-bound 5'-nucleotidase activity, but mutans streptococci did not contain the activity. The 5'-nucleotidase activity in the cell-free extract of S. sanguinis fell off significantly by the oxygen flash. Certain kind of active oxygen may be generated and inactivate the 5'-nucleotidase. AMP, GMP, UMP, deoxyAMP, deoxyCMP, deoxyGMP were decomposed by S sanguinis cells and inorganic phosphate was produced. And it was confirmed that S. sanguinis cells generated ammonia from (deoxy-)AMP, (deoxy-)CMP. In this study we found that S. sanguinis, S. gordonii and S. salivarius could metabolize extra-cellular 5'-(deoxy) ribonucleotide. It was considered that these facts are important to understand the ecosystem of the bacteria in various regions of the body as well as the dental plaque.