大连地区海生物中致病性弧菌及气单胞菌分布的研究

本文首次报道了大连地区海产品中致病性弧菌及气单胞菌生态分布的研究结果。从152份海产品中共检出88株致病性弧菌及气单胞菌,检出率为57.9％.在检查欧氏六线鱼、太平洋鲱鱼、蓝色马鲛;蝼蛄虾;紫贻贝、杂色蛤仔和毛蚶共7种海产品中,检出9种致病性弧菌和1种气单胞菌,即溶藻弧菌、副溶血性弧菌、麦氏弧菌、少女鱼弧菌、弗尼斯弧菌、拟态弧菌、河弧菌、非01群霍乱弧菌和创伤弧菌。鱼虾类中菌株的检出率明显高于贝类。检出菌株中溶藻弧菌所占比例最高(54.5％),其次为副溶血性弧菌(27.3％)。首次从海生物中分离出嗜水气单胞菌、少女鱼弧菌等致病原因菌株.     

安徽部分湖泊养殖鱼类暴发性出血病的病原分离与鉴定

目的确定引起安徽省部分湖泊养殖鱼类暴发性出血病的病原,为防治该病提供理论依据。方法随机取濒死期鲫鱼和白鲢的肌肉组织分别进行细菌和病毒分离培养,联合采用细菌表型鉴定法和16S rRNA基因序列分析法鉴定分离菌株,并使用分离菌株进行人工感染实验。结果从5尾患病鱼的肌肉组织中分离获得5株细菌,综合分离菌株的形态特征、理化特性和16S rRNA基因序列与系统发育学分析的结果,确定L1菌株为温和气单胞菌、L2菌株为维氏气单胞菌、J1、J2和L3菌株为嗜水气单胞菌。人工感染实验表明这5个气单胞菌分离株均具有较强的致病性。结论气单胞菌是该次鱼类暴发性出血病的病原,水温剧变、水质恶化和缺氧是疾病暴发的诱因,应采取改善环境、加强饲养管理、提高鱼体抵抗病力和及时杀灭病原体的综合措施防控该病。     

四株杂交鳢致病性舒伯特气单胞菌特性及致病性比较

【背景】舒伯特气单胞菌为革兰氏阴性短杆菌,是一种人-畜-鱼共患的条件性致病菌,它能引起不同程度的人类疾病,近年来更是在水产养殖中被频繁报道。【目的】比较分析4株杂交鳢源舒伯特气单胞菌(WL-4、ZL-1、ZL-13、D075)菌株间生理生化特性、致病性以及对常用药物的敏感性差异,为水产舒伯特气单胞菌病的防治提供参考依据。【方法】使用全自动细菌生化鉴定仪检测菌株的生理生化特性;运用PCR扩增和测序比对菌株的gyrB、16S rRNA基因序列;采用改良平板法检测毒力因子表达,PCR技术检测菌株毒力基因和耐药基因的携带情况;通过人工注射感染分析4株舒伯特气单胞菌对杂交鳢的致病性差异;并采用微量二倍稀释法测试15种抗菌药物对菌株的最小抑菌浓度。【结果】以ATCC43700 (人源舒伯特气单胞菌)作为参考,4株菌株理化特性基本相同,gyrB和16SrRNA基因一致性分别为99.57%和100%,聚类分析聚为一簇;不同的舒伯特气单胞菌(ATCC43700、WL-4、ZL-1、ZL-13、D075)均具有溶血性、蛋白酶活性和脂肪酶活性;但人源菌株(ATCC43700)与杂交鳢源舒伯特气单胞菌携带的毒力基因存在差异,其中人源菌株携带了hlyA、ela、lip、ahal、act,而杂交鳢源菌株(WL-4、ZL-1、ZL-13、D075)携带hlyA、ela、lip、ahal、aer;4株杂交鳢源舒伯特气单胞菌对杂交鳢致病性存在差异,1.2×10~5CFU/mL浓度腹腔注射感染健康杂交鳢,WL-4、ZL-1、ZL-13、D075对杂交鳢的感染致死率依次为30%、40%、70%和80%;不同菌株(ATCC43700、WL-4、ZL-1、ZL-13、D075)的药物敏感性以及携带的耐药基因也存在差异。【结论】4株杂交鳢源舒伯特气单胞菌在致病性、药物敏感性等方面存在差异,研究结果有助于进一步开展舒伯特气单胞菌病发病机制和防控技术研究。     

一株肠膜明串珠菌的分离鉴定及其抑菌特性

[背景] 水产病原细菌严重威胁水产动物健康且制约水产养殖业发展,细菌性鱼病的有效防治成为水产养殖领域亟待解决的问题。[目的] 筛选对水产病原细菌有抑制效果的菌株,并研究其抑菌特性及其在水产细菌病害防治中的实际效果。[方法] 通过16S rRNA基因测序、构建系统发育树和生理生化鉴定确定筛选菌株的进化地位,通过乙酸乙酯萃取获得抑菌物质粗提物,通过偶氮酪蛋白法检测菌株胞外蛋白酶活力,采用结晶紫染色法对菌株的生物膜形成能力进行测定,通过浸浴攻毒模型确定所筛菌株对维氏气单胞菌的防治作用。[结果] 从泡菜发酵物中筛选出一株乳酸菌DH,经16S rRNA基因测序、发育树分析和生理生化鉴定确定其为肠膜明串珠菌,该菌分泌的胞外抑菌物质对鼠伤寒沙门氏菌、大肠埃希氏菌、铜绿假单胞菌、杀鲑气单胞菌、希瓦氏菌和维氏气单胞菌表现出抑菌效果,其抑菌物质能被乙酸乙酯萃取并且具有热稳定性。菌株DH能够显著抑制待测菌株的蛋白酶产量和生物膜形成能力,并且对维氏气单胞菌浸浴攻毒有防治作用。[结论] 肠膜明串珠菌DH通过分泌抑菌物质抑制水产病原细菌的生长,能够为细菌性鱼病的防治提供一定的理论和应用潜力。     

长江上游网箱养殖圆口铜鱼杀鲑气单胞菌杀鲑亚种的分离与鉴定（英文）

研究首次报道了圆口铜鱼(Coreius guichenoti)疥疮病,从患病圆口铜鱼的肝脏中分离到优势菌株YTL1,并运用形态学观察、生理生化检测、16S rRNA和6个管家基因的系统发育分析等对分离菌株进行鉴定。基于以上实验结果, YTL1被最终鉴定为杀鲑气单胞菌杀鲑亚种(Aeromonas salmonicida subsp. salmonicida)。通过标准Kirby-Bauer纸片扩散法进行抗菌药物敏感性试验,筛选治疗该暴发病的有效药物,结果显示YTL1对氟苯尼考,诺氟沙星和氨苄青霉素等13种抗生素敏感,对6种抗生素如杆菌肽,链霉素和卡那霉素有耐药性,对红霉素具有中等敏感性。因此,氟苯尼考被建议用来伴饵投喂,并取得了较好的疾病控制效果。草鱼幼鱼(Ctenopharyngodon idella)和斑马鱼(Danio rerio)的人工感染试验结果显示,经腹腔注射7.6×10~6—7.6×10~8 CFU/mL的YTL1菌液后,感染鱼的症状与患病圆口铜鱼症状相似。研究证明基于6个管家基因的多序列位点分型是鉴定杀鲑气单胞菌至亚种水平的一种有效方法,杀鲑气单胞菌是圆口铜鱼人工养殖的最大威胁之一,并发现鲤科鱼类,如草鱼和斑马鱼均是杀鲑气单胞菌杀鲑亚种的易感宿主。     

长江上游网箱养殖圆口铜鱼杀鲑气单胞菌杀鲑亚种的分离与鉴定

研究首次报道了圆口铜鱼(Coreius guichenoti)疥疮病, 从患病圆口铜鱼的肝脏中分离到优势菌株YTL1, 并运用形态学观察、生理生化检测、16S rRNA和6个管家基因的系统发育分析等对分离菌株进行鉴定。基于以上实验结果, YTL1被最终鉴定为杀鲑气单胞菌杀鲑亚种(Aeromonas salmonicida subsp. salmonicida)。通过标准Kirby-Bauer纸片扩散法进行抗菌药物敏感性试验, 筛选治疗该暴发病的有效药物, 结果显示YTL1对氟苯尼考, 诺氟沙星和氨苄青霉素等13种抗生素敏感, 对6种抗生素如杆菌肽, 链霉素和卡那霉素有耐药性, 对红霉素具有中等敏感性。因此, 氟苯尼考被建议用来伴饵投喂, 并取得了较好的疾病控制效果。草鱼幼鱼(Ctenopharyngodon idella)和斑马鱼(Danio rerio)的人工感染试验结果显示, 经腹腔注射7.6×106—7.6×108 CFU/mL的YTL1菌液后, 感染鱼的症状与患病圆口铜鱼症状相似。研究证明基于6个管家基因的多序列位点分型是鉴定杀鲑气单胞菌至亚种水平的一种有效方法, 杀鲑气单胞菌是圆口铜鱼人工养殖的最大威胁之一, 并发现鲤科鱼类, 如草鱼和斑马鱼均是杀鲑气单胞菌杀鲑亚种的易感宿主。     

黄颡鱼暴发性出血病病原菌的分离鉴定及其生物膜形成特性

【背景】安徽省当涂县某池塘养殖黄颡鱼发生暴发性出血病,而当前对该病的病原存在争议。【目的】确定引起黄颡鱼暴发性出血病的病原菌,并明确分离菌株的生物膜形成特性,为从抗生物膜形成角度防治病原菌感染提供参考。【方法】取濒死期黄颡鱼病变脏器分别接种EPC细胞与培养基(TSB琼脂平板和血琼脂平板)分离病原,并通过人工感染回归试验确定其致病性;采用表型鉴定与16S rRNA基因序列分析相结合的方法鉴定分离菌株,并对其生物膜形成最佳条件、成膜能力及携带的生物膜形成相关基因进行研究。【结果】从病变脏器中分离纯化到一株优势菌株(HSY-2),对黄颡鱼的半数致死量为1.05×106 CFU/mL。经形态学、生化特性和细菌16S rRNA基因测序等分析确定分离株HSY-2为简达气单胞菌。其形成生物膜的最佳条件是将细菌接种TSB培养基于30 °C培养静置96 h,可形成中等强度的生物膜。同时,分离菌株携带气单胞菌甘油-3-磷酸脱氢酶D编码基因glpD、S-核糖同型半胱氨酸裂解酶基因luxS和LuxI家族蛋白同系物编码基因ahyI三种生物膜形成相关基因,但未检测到甘露糖敏感型血凝素菌毛合成蛋白Q编码基因。【结论】本实验为进一步研究简达气单胞菌生物膜形成的调控机制打下基础,并且从抗生物膜形成角度防治简达气单胞菌感染提供了参考。     

斑点叉尾鲖源杀鲑气单胞菌无色亚种分离鉴定及药敏特性

研究从患溃疡症斑点叉尾鲙中分离到一株致病性菌株ry01, 生理生化鉴定和16S rDNA基因序列分析表明ry01株为鲑气单胞菌无色亚种(Aeromonas salmonicida subsp. achromogenes)。人工感染该菌后发病鱼表现为与自然发病类似症状, 且从组织中再分离的细菌特性与原感染菌相同。腹腔注射后该菌株对斑点叉尾鲙的半数致死量为4.17×106 CFU/mL。菌株ry01对强力霉素及左氧氟沙星等高度敏感, 为斑点叉尾鲙该病防控提供了理论依据。     

斑点叉尾源杀鲑气单胞菌无色亚种分离鉴定及药敏特性

研究从患溃疡症斑点叉尾鲙中分离到一株致病性菌株ry01,生理生化鉴定和16S rDNA基因序列分析表明ry01株为鲑气单胞菌无色亚种(Aeromonas salmonicida subsp.achromogenes)。人工感染该菌后发病鱼表现为与自然发病类似症状,且从组织中再分离的细菌特性与原感染菌相同。腹腔注射后该菌株对斑点叉尾鲙的半数致死量为4.17×10~6 CFU/m L。菌株ry01对强力霉素及左氧氟沙星等高度敏感,为斑点叉尾鲙该病防控提供了理论依据。     

尼罗罗非鱼致病性类志贺邻单胞菌(Plesiomonas shigelloides)的分离鉴定及其病理学观察

【目的】2013年5月广东番禺某养殖场罗非鱼出现大量死亡现象,临床症状表现为鱼体体色发黑、体表出血、鳞片脱落、鳍条溃烂等,解剖发现腹腔有大量腹水、胆囊肿大、肝呈黄色、脾脏呈暗红色。为确定病原,【方法】从具以上临床症状的病鱼组织中分离获得可疑菌株1株,编号PYS1。采用形态特征、生长特性、理化特征、16S rRNA基因序列分析等理化及分子生物学技术鉴定该菌株种类。通过人工回归感染及组织病理学研究确定该菌株的致病性,并开展药物敏感性试验筛选其敏感药物。【结果】结果表明PYS1菌株为类志贺邻单胞菌(Plesiomonas shigelloides),在16S rRNA基因序列构建的分子进化树中与其他鱼源类志贺邻单胞菌聚为一支。药敏试验结果表明该菌株已呈现多重耐药性,仅对少数检测抗生素(头孢曲松、头孢洛克和头孢唑啉等)敏感。人工回归感染结果显示PYS1菌株可使尼罗罗非鱼出现与自然发病鱼相似症状,其对尼罗罗非鱼半致死量为1.425×108CFU/尾,石蜡切片显示其对感染鱼的肠、肝、脾、肾和心脏等组织均可造成损伤。【结论】证明类志贺邻单胞菌为上述养殖场尼罗罗非鱼发病的病原,且为首次报道该菌对尼罗罗非鱼的致病性。     

Isolation of enterotoxigenic Aeromonas from fish.

This paper reports two different enterotoxigenic classes of the genus Aeromonas isolated from fishes. Strains of A. sobria were isolated from healthy fishes only wheras strains of A. hydrophila were isolated from both healthy and moribund fishes. Aeromonas sobria and hydrophilia strains produced a cytotoxic factor and were highly proteolytic. Seventy-five percent (75%) of the A. sobria strains produced only one type of hemolysis on 5% blood agar, but 92% of the A. hydrophilia produced two types of hemolysis. Enterotoxigenicity of all strains was tested by the rabbit gut loop technique and the suckling mouse test. Most of those Aeromonads were enterotoxigenic. Enterotoxigenic strains appeared to produce two different enterotoxins which were antigenically related, but they seemed to have different mechanisms of action. Enterotoxins of Aeromonas were shown to be antigenically different from those of E. coli.     

湖北地区暴发病池塘中嗜水气单胞菌的遗传多样性和毒力特征研究

为了调查引起鱼类运动型气单胞菌败血症(俗称暴发病)的嗜水气单胞菌的遗传多样性和毒力特征, 阐明其流行规律, 研究于2006-2009年度从湖北省内3个不同地区的6个发病鱼塘中分离了30株嗜水气单胞菌, 其中20株为临床株(分离自血液、肝脏、肾脏或腹水), 6株为肠道株, 4株为池水株。基于所有菌株gyrB基因序列, 构建了系统发育树; 通过ERIC (Enterobacterial repetitive intergenic consensus, 肠道细菌基因间重复序列)指纹图谱进行菌株的遗传分型; 用PCR方法检测了7个毒力基因在菌株中的分布模式。这7个基因包括气溶素(aerA)、溶血素(hlyA)、热不稳定性细胞兴奋性肠毒素(alt)、热稳定性细胞兴奋性肠毒素(ast)、弹性蛋白酶(ahpB)、脂酶(lip)和鞭毛基因(fla)。此外, 以斑马鱼为感染对象, 通过腹腔注射测定了15株代表菌株的毒力。结果表明: 不同来源的20株临床株、1株肠道株和3株池水株具有相同的遗传特性, 体现为在系统树上聚为一枝, 序列相似性为100%, 具有相同的ERIC指纹图谱, 毒力基因分布模式为: aerA+hlyA+alt+ast+ahpB+lip+fla+, 且均为强毒株(LD50 9.74104cfu/尾)。与临床株相比, 其余5株肠道株和1株池水株或具有不同的ERIC指纹图谱或具有不同的毒力基因分布模式, 显示出了遗传多样性, 且毒力均弱于临床株(LD501.01106cfu/尾)。这说明在一定时间、一定区域内, 作为暴发病病原的嗜水气单胞菌为同一克隆系在流行, 不存在明显的变异或遗传多样性。此结果有助于阐明嗜水气单胞菌引起的暴发病的流行规律, 制定相应的防御措施。多种毒力基因在致病性菌株中的联合流行为发病机理的解析奠定了基础。此外, 鉴于毒力基因谱与致病性之间的相关性, 表明毒力基因可作为标记基因, 用于致病性菌株的检测。       

Assessment of genetic variability and relatedness among atypical Aeromonas salmonicida from marine fishes,using AFLP-fingerprinting

Atypical strains of Aeromonas salmonicida are the causal agent of atypical furunculosis or ulcer disease in various fish species, including spotted wolffish Anarhichas minor, which is a promising species in the Norwegian fish-farming industry. Isolates of atypical A. salmonicida comprise a very heterogenous group showing large variety in biochemical, molecular and virulence characteristics. The genetic variability among atypical isolates from wolffish was characterised using amplified fragment length polymorphism analysis: AFLP-fingerprinting. Additional isolates from halibut Hippoglossus hippoglossus, turbot Scophthalmus maximus, cod Gadus morhua and several salmonid fishes were included for assessment of variability and relatedness among a total of 56 atypical isolates of A. salmonicida. They were compared to reference strains of A. salmonicida subspecies and to other Aeromonas species pathogenic in fishes. AFLP-fingerprints subjected to similarity analysis yielded a grouping of the isolates into several clusters, revealing genetic heterogeneity among the isolates. There seems to be a correlation between genetic similarity among isolates and the fish host. The Icelandic isolates, mainly from cod, formed a very homogeneous subcluster, which was closely related to the wolffish isolates. All atypical isolates from spotted and common wolffish grouped together in a large cluster and appear to be very homogeneous, even though they had been isolated over a period of 8 yr at different locations in Norway. On the other hand, most of the isolates from turbot and halibut grouped together into 2 different clusters, while the 9 atypical isolates from salmonids appeared in 4 different clusters. Thus, the atypical isolates of A. salmonicida from halibut, turbot and salmonid fishes seem to be more genetically diverse than those from wolffish and cod.     

Incidence and identification of mesophilic Aeromonas spp. from retail foods

Sixty-eight food samples were examined for the presence of mesophilic Aeromonas species both qualitatively and quantitatively. Aeromonads were isolated from 26% of the vegetable samples, 70% of the meat and poultry samples and 72% of the fish and shrimps. Numbers of motile aeromonads present in the food samples varied from <10(2) cfu g(-1) to >10(5) cfu g(-1). GLC analysis of FAMEs was used to identify a selection of presumptive Aeromonas colonies to fenospecies or genomic species level. Aeromonas strains belonging to the Aer. caviae complex, which also includes the potentially pathogenic genospecies HG4, were mostly isolated from vegetables but were also found in meat, poultry and fish. In addition, three strains of the virulent taxon Aer. veronii biovar sobria HG8 were isolated from poultry and minced meat. All members of the Aer. hydrophila complex, predominant in the fish, meat and poultry samples, were classified in the non-virulent taxon HG3. Although the significance of Aeromonas in foods remains undefined, the isolation of Aeromonas HG4 and HG8 strains from a variety of retail foods may indicate that these products can act as possible vehicles for the dissemination of food-borne Aeromonas gastroenteritis.     

广东中山地区气单胞菌环境株的分离、鉴定及系统发生关系

从广东省中山市的池塘水样、底泥、健康鱼、肠道及稻田土样中用Aeromonas的选择培养基分离到10株气单胞菌。通过生理生化测试、16S rDNA序列测定、与气单胞菌典型菌株的16S rDNA序列进行比对和聚类分析,对它们进行了鉴定,并研究了它们之间的系统发生关系。结果显示该地区环境中气单胞菌的优势种除A.hydrophila(HG1组)外,还有A.caviae(HG4组)、A.jandaei(HG9组)和A.veronii(HG10组),其中后两种是国内新记录。这是国内首次对环境中气单胞菌多样性进行研究。     

引起鱼类暴发性流行病的嗜水气单胞菌的血清型、毒力及溶血性

对分离自暴发病鱼的33株嗜水气单胞菌株的血清型、毒力和溶血性进行了研究。结果表明:按O抗原不同,大部分菌株可分为TPS-30和PBJS-76两个血清型,这两个血清型菌株分布于浙江各地及南方其它省市,可能是构成暴发病流行嗜水气单胞的主要血清型;这些菌株对健康白鲫有很强致病力,LD₅₀小于10⁶,有很强的产溶血素能力,但某些菌株的毒力与其溶血效价无直接联系。     

西伯利亚鲟致病性嗜水气单胞菌外膜蛋白及其抗原性分析

采用十二烷基肌氨酸钠(Sarkosyl)法提取西伯利亚鲟嗜水气单胞菌(Aeromonas hydrophila)外膜蛋白,电泳显示所提取的主要外膜蛋白分子量为26～120 kDa;为比较该菌株与气单胞菌菌属其他细菌外膜蛋白组分及抗原性异同,以致病性豚鼠气单胞菌(A.caviae)、温和气单胞菌(A.sobria)和无致病力的嗜水气单胞菌为对照,电泳图谱显示4种气单胞菌外膜蛋白的分子量主要集中在26～120 kDa之间;利用抗西伯利亚鲟嗜水气单胞菌血清的免疫印迹试验表明该菌株外膜蛋白中分子量为75 kDa、52 kDa、43 kDa、40 kDa、34 kDa、28 kDa的蛋白条带呈现阳性反应,其他3种气单胞菌外膜蛋白中均有与该抗血清反应的条带,且分子量为28 kDa、34 kDa的反应条带为4株菌共有;43 kDa与75 kDa反应条带为部分菌株共有.为进一步筛选和研究致病性气单胞菌的共同保护抗原提供参考.     

Characterization of Aeromonas salmonicida subsp. salmonicida: a comparative study of strains of different geographic origin

A total of 130 strains of the fish pathogen Aeromonas salmonicida isolated in Denmark, Norway, Scotland, Canada and the USA were examined. The strains originated from farmed salmonid fish. The biochemical, physiological and serological characteristics, antibiotic resistance patterns and cell surface-related properties were compared. Aeromonas salmonicida was found to be remarkably consistent in general cultural and biochemical characteristics. It is noteworthy that the strains were positive in the fermentation of L-arabinose and were negative in the fermentation of D-arabinose. All the strains were highly proteolytic. It was observed, however, that 5% of the strains did not digest calf and trout serum and the production of haemolysin and degradation of casein by the same strains were delayed compared with the other strains. Common to all of the rough strains were auto-aggregation and ability to bind the dyes Coomassie brilliant blue and Congo red and the majority of these strains were highly hydrophobic. The strains were tested for their susceptibility to 22 antibacterial agents. Antibiotic resistance profiles of Aer. salmonicida indicated that resistance to the quinolones and oxytetracycline was increasing and that multi-resistant strains were found in several countries. The variation found in antibiograms could have potential as epidemiological markers in certain geographic areas.     

Effect of Aeromonas proteases on the binding of Aeromonas hydrophila strains to connective tissue proteins

125I-labelled connective tissue protein binding to cells of Aeromonas hydrophila, A. caviae, and A. sobria strains isolated from diseased fish, was correlated with the Aeromonas protease degradation of 125I-labelled collagen types I and IV, fibronectin and laminin, immobilized on tissue culture microtitre plates. An inverse relation between 125I-labelled connective tissue protein binding to cells of Aeromonas strains and proteolytic degradation of immobilized connective tissue proteins by Aeromonas proteases was established. Inhibition of the Aeromonas proteolytic activity by protease inhibitors enhances the 125I-labelled connective tissue protein binding to cells of Aeromonas hydrophila strains. Culture conditions were found to influence both expression of proteolytic activity and binding properties.     

Determination of microbial diversity of Aeromonas strains on the basis of multilocus sequence typing, phenotype, and presence of putative virulence genes

The genus Aeromonas has been described as comprising several species associated with the aquatic environment, which represents their principal reservoir. Aeromonas spp. are commonly isolated from diseased and healthy fish, but the involvement of such bacteria in human infection and gastroenteritis has frequently been reported. The primary challenge in establishing an unequivocal link between the Aeromonas genus and pathogenesis in humans is the extremely complicated taxonomy. With the aim of clarifying taxonomic relationships among the strains and phenotypes, a multilocus sequencing approach was developed and applied to characterize 23 type and reference strains of Aeromonas spp. and a collection of 77 field strains isolated from fish, crustaceans, and mollusks. All strains were also screened for putative determinants of virulence by PCR (ast, ahh1, act, asa1, eno, ascV, and aexT) and the production of acylated homoserine lactones (AHLs). In addition, the phenotypic fingerprinting obtained from 29 biochemical tests was submitted to the nonparametric combination (NPC) test methodology to define the statistical differences among the identified genetic clusters. Multilocus sequence typing (MLST) achieved precise strain genotyping, and the phylogenetic analysis of concatenated sequences delineated the relationship among the taxa belonging to the genus Aeromonas, providing a powerful tool for outbreak traceability, host range diffusion, and ecological studies. The NPC test showed the feasibility of phenotypic differentiation among the majority of the MLST clusters by using a selection of tests or the entire biochemical fingerprinting. A Web-based MLST sequence database (http://pubmlst.org/aeromonas) specific for the Aeromonas genus was developed and implemented with all the results.