USDA, ARS, WRRC, Produce Safety and Microbiology Albany, CA, USA.
Front Cell Infect Microbiol. 2012 Apr 2;2:45. doi: 10.3389/fcimb.2012.00045. eCollection 2012.
Multilocus sequence typing (MLST) systems have been reported previously for multiple food- and food animal-associated Campylobacter species (e.g., C. jejuni, C. coli, C. lari, and C. fetus) to both differentiate strains and identify clonal lineages. These MLST methods focused primarily on campylobacters of human clinical (e.g., C. jejuni) or veterinary (e.g., C. fetus) relevance. However, other, emerging, Campylobacter species have been isolated increasingly from environmental, food animal, or human clinical samples. We describe herein four MLST methods for five emerging Campylobacter species: C. hyointestinalis, C. lanienae, C. sputorum, C. concisus, and C. curvus. The concisus/curvus method uses the loci aspA, atpA, glnA, gltA, glyA, ilvD, and pgm, whereas the other methods use the seven loci defined for C. jejuni (i.e., aspA, atpA, glnA, gltA, glyA, pgm, and tkt). Multiple food animal and human clinical C. hyointestinalis (n = 48), C. lanienae (n = 34), and C. sputorum (n = 24) isolates were typed, along with 86 human clinical C. concisus and C. curvus isolates. A large number of sequence types were identified using all four MLST methods. Additionally, these methods speciated unequivocally isolates that had been typed ambiguously using other molecular-based speciation methods, such as 16S rDNA sequencing. Finally, the design of degenerate primer pairs for some methods permitted the typing of related species; for example, the C. hyointestinalis primer pairs could be used to type C. fetus strains. Therefore, these novel Campylobacter MLST methods will prove useful in differentiating strains of multiple, emerging Campylobacter species.
多位点序列分型（MLST）系统先前已被报道用于多种食源和食源相关的弯曲菌属物种（例如空肠弯曲菌、大肠弯曲菌、海鸥弯曲菌和胎儿弯曲菌），以区分菌株和识别克隆谱系。这些 MLST 方法主要侧重于与人类临床（例如空肠弯曲菌）或兽医（例如胎儿弯曲菌）相关的弯曲菌。然而，其他新兴的弯曲菌属物种也越来越多地从环境、食源动物或人类临床样本中分离出来。本文描述了用于五种新兴弯曲菌属物种的四种 MLST 方法：C. hyointestinalis、C. lanienae、C. sputorum、C. concisus 和 C. curvus。concisus/curvus 方法使用 aspA、atpA、glnA、gltA、glyA、ilvD 和 pgm 基因座，而其他方法使用空肠弯曲菌定义的七个基因座（即 aspA、atpA、glnA、gltA、glyA、pgm 和 tkt）。对多种食源动物和人类临床的 C. hyointestinalis（n=48）、C. lanienae（n=34）和 C. sputorum（n=24）分离株进行了分型，同时还对 86 株人类临床的 C. concisus 和 C. curvus 分离株进行了分型。使用所有四种 MLST 方法鉴定了大量的序列型。此外，这些方法明确地对使用其他分子分类方法（如 16S rDNA 测序）进行分类鉴定存在歧义的分离株进行了分类。最后，一些方法的简并引物对的设计允许对相关物种进行分型；例如，可以使用 C. hyointestinalis 引物对对胎儿弯曲菌菌株进行分型。因此，这些新的弯曲菌属 MLST 方法将有助于区分多种新兴的弯曲菌属物种的菌株。
