Mora Azucena, Blanco Miguel, Blanco Jesús E, Alonso M Pilar, Dhabi Ghizlane, Thomson-Carter Fiona, Usera Miguel A, Bartolomé Rosa, Prats Guillermo, Blanco Jorge
Laboratorio de Referencia de E. coli, Facultad de Veterinaria, Universidad de Santiago de Compostela, Lugo, Spain.
J Clin Microbiol. 2004 Sep;42(9):4007-15. doi: 10.1128/JCM.42.9.4007-4015.2004.
Phage typing and DNA macrorestriction fragment analysis by pulsed-field electrophoresis (PFGE) were used for the epidemiological subtyping of a collection of Shiga toxin-producing Escherichia coli (STEC) O157:H7 strains isolated in Spain between 1980 and 1999. Phage typing distinguished a total of 18 phage types among 171 strains isolated from different sources (67 humans, 82 bovines, 12 ovines, and 10 beef products). However, five phage types, phage type 2 (PT2; 42 strains), PT8 (33 strains), PT14 (14 strains), PT21/28 (11 strains), and PT54 (16 strains), accounted for 68% of the study isolates. PT2 and PT8 were the most frequently found among strains from both humans (51%) and bovines (46%). Interestingly, we detected a significant association between PT2 and PT14 and the presence of acute pathologies. A group of 108 of the 171 strains were analyzed by PFGE, and 53 distinct XbaI macrorestriction patterns were identified, with 38 strains exhibiting unique PFGE patterns. In contrast, phage typing identified 15 different phage types. A total of 66 phage type-PFGE subtype combinations were identified among the 108 strains. PFGE subtyping differentiated between unrelated strains that exhibited the same phage type. The most common phage type-PFGE pattern combinations were PT2-PFGE type 1 (1 human and 11 bovine strains), PT8-PFGE type 8 (2 human, 6 bovine, and 1 beef product strains), PT2-PFGE subtype 4A (1 human, 3 bovine, and 1 beef product strains). Nine (29%) of 31 human strains showed phage type-PFGE pattern combinations that were detected among the bovine strains included in this study, and 26 (38%) of 68 bovine strains produced phage type-PFGE pattern combinations observed among human strains included in this study, confirming that cattle are a major reservoir of strains pathogenic for humans. PT2 and PT8 strains formed two groups which differed from each other in their motilities, stx genotypes, PFGE patterns, and the severity of the illnesses that they caused.
采用噬菌体分型和脉冲场凝胶电泳（PFGE）进行DNA宏限制性片段分析，对1980年至1999年间在西班牙分离出的一组产志贺毒素大肠杆菌（STEC）O157:H7菌株进行流行病学亚型分析。噬菌体分型在从不同来源分离出的171株菌株（67株来自人类、82株来自牛、12株来自羊和10株来自牛肉制品）中总共区分出18种噬菌体类型。然而，5种噬菌体类型，即噬菌体类型2（PT2；42株）、PT8（33株）、PT14（14株）、PT21/28（11株）和PT54（16株），占研究分离株的68%。PT2和PT8在来自人类（51%）和牛（46%）的菌株中最为常见。有趣的是，我们检测到PT2和PT14与急性病理的存在之间存在显著关联。对171株菌株中的108株进行了PFGE分析，鉴定出53种不同的XbaI宏限制性图谱，其中38株表现出独特的PFGE图谱。相比之下，噬菌体分型鉴定出15种不同的噬菌体类型。在108株菌株中总共鉴定出66种噬菌体类型 - PFGE亚型组合。PFGE亚型分析区分了表现出相同噬菌体类型的不相关菌株。最常见的噬菌体类型 - PFGE图谱组合是PT2 - PFGE类型1（1株来自人类和11株来自牛的菌株）、PT8 - PFGE类型8（2株来自人类、6株来自牛和1株来自牛肉制品的菌株）、PT2 - PFGE亚型4A（1株来自人类、3株来自牛和1株来自牛肉制品的菌株）。31株人类菌株中有9株（29%）显示出在本研究纳入的牛菌株中检测到过的噬菌体类型 - PFGE图谱组合，68株牛菌株中有26株（38%）产生了在本研究纳入的人类菌株中观察到过的噬菌体类型 - PFGE图谱组合，这证实牛是人类致病菌株的主要储存宿主。PT2和PT8菌株形成了两组，它们在运动性、stx基因型、PFGE图谱以及它们所引起疾病的严重程度方面彼此不同。
