摘要
李斯特菌属包含6个种,毒力各有差异。在细菌耐受外界环境、黏附侵袭及细胞内感染过程中,毒力因子各司其职又相互协作。毒力基因常聚集为毒力岛,其中PrfA依赖型毒力基因簇(LIPI-1)与内化素岛(LIPI-2)是致病种最重要的两个毒力岛。李斯特菌各个种可能来源于同一个携带有完整毒力岛的祖先,在长期进化过程中,通过基因水平转移或重组、整合等事件,演化为目前流行的6个种。噬菌体、转座子、质粒等可能扮演着毒力进化执行者的角色。一些天然非典型菌株是目前研究的热点,如含有LIPI-1的无害李斯特菌和缺失LIPI-1的塞氏李斯特菌,其演化进程可能尚未达到或已超越目前流行的状态,为李斯特菌毒力进化的研究提供了重要线索。
The genus Listeria consists of six species： L. monocytogenes, L. innocua, L. welshimeri, L. ivanovii, L. seeligeri and L. grayi. Two of the species, L. monocytogenes and L. ivanovii are pathogenic. The heterogeneity of remaining species, previously assumed to be nonpathogenic, regarding their capability of acquiring virulence-associated genes may reflect their potential ability to be causative agents of diseases, especially in immunocompromised mannals. Virulence determinants involved in environmental tolerance, adhesion and invasion of eukaryotic cells and intracellular life function interactively. The virulence genes are mostly organized into discrete genetic units known as pathogenicity islands （PAIs）, among which Listeria pathogenicity island 1 （LIPI-1） and island 2 （LIPI-2） are the most important. During the evolution of pathogenicity, a common ancestor bearing PAIs gave rise to the currently prevailing typical strains of six species through horizontal transfer of virulence determinants or by events such as recombination and natural selection. Compred harbored nonhemol fruitful insights into the evolution events of pathogenicity underlying the phylogeny of the genus Listeria.
出处
《微生物学报》
CAS
CSCD
北大核心
2007年第4期738-742,共5页
Acta Microbiologica Sinica
关键词
李斯特菌
毒力因子
毒力进化
非典型菌株
Listeria
virulence determinants
evolution of pathogeneity
atypical strains
