Pinho M D, Melo-Cristino J, Ramirez M
Instituto de Microbiologia, Faculdade de Medicina de Lisboa, Av. Prof. Egas Moniz, PT 1649-028 Lisbon, Portugal.
J Clin Microbiol. 2006 Mar;44(3):841-6. doi: 10.1128/JCM.44.3.841-846.2006.
Lancefield group G and group C streptococci (GGS and GCS, respectively) are pathogens responsible for a number of life-threatening infections. A collection of 116 recent (1998 to 2004) invasive (n = 28) and noninvasive (n = 88) GGS and GCS clinical isolates from Portugal were characterized. All isolates were identified as Streptococcus dysgalactiae subsp. equisimilis and characterized by emm typing and DNA macrorestriction profiling using pulsed-field gel electrophoresis (PFGE). emm typing revealed the presence of 22 distinct types, including 3 novel types. PFGE identified 14 clones with more than two isolates, but over half of the isolates were concentrated in 3 large clones. Individual clones and emm types showed a low level of association, since the majority of the clones included more than one emm type and the same emm type was found among diverse genetic backgrounds. Two emm types, stg2078 and stg10, were significantly more frequent among invasive isolates, and another two, stg6792 and stg166b, were present only in noninvasive isolates, suggesting a correlation between emm type and invasive disease potential.
兰斯菲尔德G群和C群链球菌（分别为GGS和GCS）是导致多种危及生命感染的病原体。对葡萄牙近期（1998年至2004年）收集的116株侵袭性（n = 28）和非侵袭性（n = 88）GGS和GCS临床分离株进行了特征分析。所有分离株均鉴定为马链球菌兽疫亚种，并通过emm分型和使用脉冲场凝胶电泳（PFGE）的DNA宏观限制性图谱分析进行特征描述。emm分型显示存在22种不同类型，包括3种新类型。PFGE鉴定出14个含有两个以上分离株的克隆，但超过一半的分离株集中在3个大克隆中。单个克隆和emm类型之间的关联程度较低，因为大多数克隆包含不止一种emm类型，并且在不同的遗传背景中发现了相同的emm类型。两种emm类型，stg2078和stg10，在侵袭性分离株中显著更常见，另外两种，stg6792和stg166b，仅存在于非侵袭性分离株中，表明emm类型与侵袭性疾病潜力之间存在相关性。
