CAJ | 학술논문

目的研究变形链球菌代谢产生活性氧的规律及其酶学基础，探讨变形链球菌活性氧代谢产物对菌斑微生态的作用。方法采用电子自旋捕捉法检测不同培养条件下变形链球菌产生活性氧的情况及还原型尼克酰胺腺嘌呤二核苷酸（nicotinamide adenine dinucleotide reduced，NADH）对次黄嘌呤-黄嘌呤氧化酶体系和Fe2+-H2O2体系产生活性氧的影响。结果在变形链球菌培养液中可检测到特征性的二甲基吡咯氮氧化物（dimethyl pyridine N-oxide，DMPO）-O2和DMPO-OH·的电子自旋共振（electron spin resonance，ESR）信号及超氧化物歧化酶的活性；美蓝使变形链球菌培养过程中产生的特征性ESR信号消失；NADH对变形链球菌培养过程中产生的特征性ESR信号没有明显影响，但是NADH可使次黄嘌呤-黄嘌呤氧化酶体系和Fe2+-H2O2体系的ESR信号明显减弱甚至消失。结论变形链球菌在代谢过程中产生了O2和OH·，NADH氧化酶催化的反应可能是变形链球菌产生活性氧的主要来源。
목적연구변형련구균대사산생활성양적규률급기매학기출，탐토변형련구균활성양대사산물대균반미생태적작용。방법채용전자자선포착법검측불동배양조건하변형련구균산생활성양적정황급환원형니극선알선표령이핵감산（nicotinamide adenine dinucleotide reduced，NADH）대차황표령-황표령양화매체계화Fe2+-H2O2체계산생활성양적영향。결과재변형련구균배양액중가검측도특정성적이갑기필각담양화물（dimethyl pyridine N-oxide，DMPO）-O2화DMPO-OH·적전자자선공진（electron spin resonance，ESR）신호급초양화물기화매적활성；미람사변형련구균배양과정중산생적특정성ESR신호소실；NADH대변형련구균배양과정중산생적특정성ESR신호몰유명현영향，단시NADH가사차황표령-황표령양화매체계화Fe2+-H2O2체계적ESR신호명현감약심지소실。결론변형련구균재대사과정중산생료O2화OH·，NADH양화매최화적반응가능시변형련구균산생활성양적주요래원。
Objective　To study the rules of Streptococcus mutans reactive oxygen species metabolism and its enzymatic basis, and to investigate its significance intermediate to plaque microbial ecology. Methods　Electron spin trapping method was used to measure reactive oxygen species produced by Streptococcus mutans in the different incubation conditions, and evaluate the efficicay of NADH to hypoxanthine-xanthine oxidase and Fe2+-H2O2 system. Results　Electron spin resonance (ESR) spectrum of DMPO-O2－and DMPO-OH. And superoxide dismutase were obtained in Streptococcus mutans culture fluid, these spectrum were strengthened by exogenous sugar, and disappeared when methylene blue was added to culture fluid, but that spectrum was not significantly changed by NADH. ESR spectrum of hypoxanthine-xanthine oxidase and Fe2+-H2O2system were significantly reduced or disappeared by NADH. Conclusion　These results suggest that there are O2 and OH· in Streptococcus mutans metabolism, and they may come mainly from the reaction catalyzed by NADH oxidase.