中华微生物学和免疫学杂志
中華微生物學和免疫學雜誌
중화미생물학화면역학잡지
CHINESE JOURNAL OF MICROBIOLOGY AND IMMUNOLOGY
2010年
7期
608-612
,共5页
变异链球菌%LuxS基因%耐酸能力%密度感应
變異鏈毬菌%LuxS基因%耐痠能力%密度感應
변이련구균%LuxS기인%내산능력%밀도감응
Streptococcus mutans%LuxS gene%Acid tolerance%Quorum sensing
目的 建立LuxS基因缺失的变异链球菌突变菌株,并对突变株的耐酸能力进行研究.方法 以变异链球菌UA159为材料,运用基因重组方法将红霉素抗性基因(Eymr)与LuxS基因上下游区域的2个基因片段按一定顺序重组到质粒载体PUC19的多克隆位点中,获得了具有红霉素抗性的重组质粒,将载体质粒转化到含完整LuxS基因的变异链球菌UA159中,利用红霉素抗性筛选出LuxS基因缺失的突变株.检测变异链球菌LuxS基因突变菌株在不同pH环境下生长情况,并以正常菌株为对照.结果 PCR基因扩增结果显示,突变株LuxS基因已被Eymr基因完全替换,不能再编码合成AI-2(autoinducer 2)信号分子,扩增产物经DNA测序证实筛选得到了LuxS基因缺失的突变株,并且突变株不能诱导V.harveyi BB170的生物发光.与变异链球菌标准菌株相比,LuxS基因突变株的生长情况随着pH的降低受到明显抑制.结论 本研究成功构建LuxS基因缺失的变异链球菌突变株,LuxS感应信号系统参与变异链球菌耐酸能力的调控,LuxS基因缺失菌株耐酸能力降低.
目的 建立LuxS基因缺失的變異鏈毬菌突變菌株,併對突變株的耐痠能力進行研究.方法 以變異鏈毬菌UA159為材料,運用基因重組方法將紅黴素抗性基因(Eymr)與LuxS基因上下遊區域的2箇基因片段按一定順序重組到質粒載體PUC19的多剋隆位點中,穫得瞭具有紅黴素抗性的重組質粒,將載體質粒轉化到含完整LuxS基因的變異鏈毬菌UA159中,利用紅黴素抗性篩選齣LuxS基因缺失的突變株.檢測變異鏈毬菌LuxS基因突變菌株在不同pH環境下生長情況,併以正常菌株為對照.結果 PCR基因擴增結果顯示,突變株LuxS基因已被Eymr基因完全替換,不能再編碼閤成AI-2(autoinducer 2)信號分子,擴增產物經DNA測序證實篩選得到瞭LuxS基因缺失的突變株,併且突變株不能誘導V.harveyi BB170的生物髮光.與變異鏈毬菌標準菌株相比,LuxS基因突變株的生長情況隨著pH的降低受到明顯抑製.結論 本研究成功構建LuxS基因缺失的變異鏈毬菌突變株,LuxS感應信號繫統參與變異鏈毬菌耐痠能力的調控,LuxS基因缺失菌株耐痠能力降低.
목적 건립LuxS기인결실적변이련구균돌변균주,병대돌변주적내산능력진행연구.방법 이변이련구균UA159위재료,운용기인중조방법장홍매소항성기인(Eymr)여LuxS기인상하유구역적2개기인편단안일정순서중조도질립재체PUC19적다극륭위점중,획득료구유홍매소항성적중조질립,장재체질립전화도함완정LuxS기인적변이련구균UA159중,이용홍매소항성사선출LuxS기인결실적돌변주.검측변이련구균LuxS기인돌변균주재불동pH배경하생장정황,병이정상균주위대조.결과 PCR기인확증결과현시,돌변주LuxS기인이피Eymr기인완전체환,불능재편마합성AI-2(autoinducer 2)신호분자,확증산물경DNA측서증실사선득도료LuxS기인결실적돌변주,병차돌변주불능유도V.harveyi BB170적생물발광.여변이련구균표준균주상비,LuxS기인돌변주적생장정황수착pH적강저수도명현억제.결론 본연구성공구건LuxS기인결실적변이련구균돌변주,LuxS감응신호계통삼여변이련구균내산능력적조공,LuxS기인결실균주내산능력강저.
Objective To construct Streptococcus mutans UA159 mutants with deletion of LuxS gene related to quorum-sensing pathway and evaluate the aciduricity of the mutants. Methods Using S. mutans UA159 as materials, the PCR fragments of the upstream and downstream regions of LuxS and erythromycin resistance(Eymr) gene of PJT10 were cloned into plasmid PUC19. The resulting constructs were integrated into the chromosome of S. mutans. LuxS gene deletion mutant was then constructed in S. mutans by means of allelic exchange and selected for resistance to erythromycin. The aciduric ability of the mutant under different pH was measured and S. mutans UA159 was used as control. Results The LuxS-deleted status of S. mutans mutants were confirmed by various PCR and DNA sequencing. The results showed that Eymr gene take the place of LuxS gene, while the mutant can not induce bioluminescenece. The LuxS mutant strain displayed a decreased growth ability with the decreasing pH values compared to those of the wild-type strain UA159. Conclusion A LuxS-negative mutants of S. mutans is constructed. The LuxS quorum sensing system is involved in the regulation of aciduricity of S. mutans UA159.
