Morales Cesar A, Porwollik Steffen, Frye Jonathan G, Kinde Hailu, McClelland Michael, Guard-Bouldin Jean
Egg Safety and Quality Research Unit, Agricultural Research Service, U.S. Department of Agriculture, 950 College Station Rd., Athens, GA 30605, USA.
Appl Environ Microbiol. 2005 Aug;71(8):4388-99. doi: 10.1128/AEM.71.8.4388-4399.2005.
The genotype of Salmonella enterica serovar Enteritidis was correlated with the phenotype using DNA-DNA microarray hybridization, ribotyping, and Phenotype MicroArray analysis to compare three strains that differed in colony morphology and phage type. No DNA hybridization differences were found between two phage type 13A (PT13A) strains that varied in biofilm formation; however, the ribotype patterns were different. Both PT13A strains had DNA sequences similar to that of bacteriophage Fels2, whereas the PT4 genome to which they were compared, as well as a PT4 field isolate, had a DNA sequence with some similarity to the bacteriophage ST64b sequence. Phenotype MicroArray analysis indicated that the two PT13A strains and the PT4 field isolate had similar respiratory activity profiles at 37 degrees C. However, the wild-type S. enterica serovar Enteritidis PT13A strain grew significantly better in 20% more of the 1,920 conditions tested when it was assayed at 25 degrees C than the biofilm-forming PT13A strain grew. Statistical analysis of the respiratory activity suggested that S. enterica serovar Enteritidis PT4 had a temperature-influenced dimorphic metabolism which at 25 degrees C somewhat resembled the profile of the biofilm-forming PT13A strain and that at 37 degrees C the metabolism was nearly identical to that of the wild-type PT13A strain. Although it is possible that lysogenic bacteriophage alter the balance of phage types on a farm either by lytic competition or by altering the metabolic processes of the host cell in subtle ways, the different physiologies of the S. enterica serovar Enteritidis strains correlated most closely with minor, rather than major, genomic changes. These results strongly suggest that the pandemic of egg-associated human salmonellosis that came into prominence in the 1980s is primarily an example of bacterial adaptive radiation that affects the safety of the food supply.
利用DNA - DNA微阵列杂交、核糖体分型和表型微阵列分析，将肠炎沙门氏菌肠炎血清型的基因型与表型进行关联，以比较三株在菌落形态和噬菌体类型上存在差异的菌株。在两株生物膜形成能力不同的噬菌体13A（PT13A）菌株之间未发现DNA杂交差异；然而，核糖体分型模式不同。两株PT13A菌株都具有与噬菌体Fels2相似的DNA序列，而与之比较的PT4基因组以及一株PT4现场分离株具有与噬菌体ST64b序列有些相似的DNA序列。表型微阵列分析表明，两株PT13A菌株和PT4现场分离株在37℃时具有相似的呼吸活性谱。然而，野生型肠炎沙门氏菌肠炎血清型PT13A菌株在25℃下进行检测时，在1920种测试条件中的20%以上条件下生长明显优于形成生物膜的PT13A菌株。呼吸活性的统计分析表明，肠炎沙门氏菌肠炎血清型PT4具有受温度影响的双态代谢，在25℃时 somewhat resembled形成生物膜的PT13A菌株的谱，在37℃时其代谢与野生型PT13A菌株几乎相同。尽管溶源性噬菌体有可能通过溶菌竞争或以微妙方式改变宿主细胞的代谢过程来改变农场中噬菌体类型的平衡，但肠炎沙门氏菌肠炎血清型菌株的不同生理学特征与微小而非主要的基因组变化最密切相关。这些结果强烈表明，20世纪80年代突出的与鸡蛋相关的人类沙门氏菌病大流行主要是影响食品供应安全的细菌适应性辐射的一个例子。
