CAJ | 학술논문

采用TCBS选择性培养基从厦门某鲍鱼养殖场的养殖水体中分离到19株细菌．经16S rDNA序列分析，所有菌株均属于弧菌属（Vibrio），且与最近似的弧菌模式种的同源性都在98．99％以上．由于弧菌种间16S rDNA序列相似度极高，无法仅靠16S rDNA序列比对来鉴定这些菌株到种的水平．16S rDNA序列的系统发育分析也显示，大多数菌株与弧菌模式种无法归为一簇，表明16S rD-NA基因在弧菌种的分类鉴定上分辨率不高．进一步采用基于4种看家基因（rpoA、pyrH、gapA和to-pA）的多位点序列分析技术（MLSA）对分离到的弧菌菌株进行分类鉴定，结果显示19株海洋弧菌归于溶藻弧菌（Vibrio alginalyticus）与魔鬼弧菌（Vibrio diabolicus）2个种，表明这两种弧菌是该鲍鱼养殖场水体环境中的优势弧菌种，在鲍鱼养殖弧菌病害防治方面需要重点关注．此外，看家基因与16S rDNA基因的多态性分析表明，4种看家基因的多态位点比率均高于16S rDNA．4种看家基因串联后的多态位点比率高达41．1％，远高于16S rDNA基因的13．4％，表明看家基因相较于16S rDNA基因有着更高的分辨率，更适合于海洋弧菌的分类鉴定．
채용TCBS선택성배양기종하문모포어양식장적양식수체중분리도19주세균．경16S rDNA서렬분석，소유균주균속우호균속（Vibrio），차여최근사적호균모식충적동원성도재98．99％이상．유우호균충간16S rDNA서렬상사도겁고，무법부고16S rDNA서렬비대래감정저사균주도충적수평．16S rDNA서렬적계통발육분석야현시，대다수균주여호균모식충무법귀위일족，표명16S rD-NA기인재호균충적분류감정상분변솔불고．진일보채용기우4충간가기인（rpoA、pyrH、gapA화to-pA）적다위점서렬분석기술（MLSA）대분리도적호균균주진행분류감정，결과현시19주해양호균귀우용조호균（Vibrio alginalyticus）여마귀호균（Vibrio diabolicus）2개충，표명저량충호균시해포어양식장수체배경중적우세호균충，재포어양식호균병해방치방면수요중점관주．차외，간가기인여16S rDNA기인적다태성분석표명，4충간가기인적다태위점비솔균고우16S rDNA．4충간가기인천련후적다태위점비솔고체41．1％，원고우16S rDNA기인적13．4％，표명간가기인상교우16S rDNA기인유착경고적분변솔，경괄합우해양호균적분류감정．
A total of 19 bacterial strains were isolated from aquaculture water of an abalone farm in Xiamen.All these strains were identified as Vibrio spp.based on 16S rDNA gene sequence analysis.Their 16S rDNA sequences showed high degrees of similarity (≥98.99%)with closest matched reference sequences of Vibrio type species. However,due to extreme high similarity of 16S rDNA sequences among Vibrio species,it was impossible to identify these Vibrio strains to species level only based on 16S rDNA sequence analysis.Phylogenteic analysis also showed that most 16S rDNA sequences of these isolates were not grouped with the reference sequences of Vibrio type spe-cies,suggesting that 16S rDNA gene is not adequate for resolution of Vibrio species.Multilocus sequence analysis of 4 housekeeping genes (rpoA,pyrH,gapA,and topA)was further performed to identify these Vibrio isolates.The results showed that 19 isolates belong to two Vibrio species,Vibrio alginalyticus and Vibrio diabolicus,indicating that these two Vibrio species are dominant in aquaculture water of the abalone farm.Polymorphism analysis demon-strated that all of 4 housekeeping genes showed higher polymorphic sites than the 16S rDNA gene.The concatena-ted sequences of 4 housekeeping genes exhibited 41.1%of polymorphic sites,much higher than that of 16S rDNA (13.4%).These results suggested that the housekeeping genes showed remarkable higher solution than 16S rDNA gene for species identification of marine Vibrios.