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目的观察抗生素对幽门螺杆菌(HP)细胞壁的影响。方法将培养至对数生长期的HP两菌株NCTC11637、SS1接种至含不同浓度的阿莫西林、甲硝唑、红霉素或左氧氟沙星的液体培养基中,置37℃微需氧培养3-5d,以0.22μm滤菌器过滤,需氧条件下培养至出现球形体后传代。传5-8代后收集球形体并提取DNA进行16SrDNA片段PCR扩增电泳。结果体外NCTC11637和SS1在4种抗生素作用下均可发生细胞壁缺陷,形成L型;L型HP可通过0.22μm滤菌器,并可在液体培养基内生长;L型HP的DNA可扩增出与亲代细菌型分子量一致的16SrDNA片段。结论抗生素可诱导HP发生细胞壁缺陷变异。不规范使用抗生素可能导致体内HP形成L型,可能是胃部疾病反复发作的原因之一。
Objective To observe the effect of antibiotics on the cell wall of Helicobacter pylori (HP). Methods HPTC strain NCTC11637 was cultivated to logarithmic growth phase. SS1 was inoculated into liquid medium containing different concentrations of amoxicillin, metronidazole, erythromycin or levofloxacin, and cultured at 37 ℃ for 3-5 days , Filtered with a 0.22μm filter, and cultured under aerobic conditions until the spheroids appeared. After 5-8 passages, spheroids were collected and DNA extracted for 16S rDNA fragment PCR amplification. Results In vitro, NCTC11637 and SS1 could induce cell wall defects under the action of four antibiotics to form L-form. L-type HP could pass through 0.22μm filter and grow in liquid medium. DNA of L-type HP could be amplified 16SrDNA fragment consistent with the parental bacterial type molecular weight. Conclusion Antibiotics can induce HP cell wall defects. Irregular use of antibiotics may lead to the formation of L-form HP in vivo, may be one of the causes of recurrent gastric disease.