کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2468593 1112022 2009 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
The putative penicillin-binding proteins 1 and 2 are important for viability, growth and cell morphology of Brucella melitensis
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم کشاورزی و بیولوژیک علوم دامی و جانورشناسی
پیش نمایش صفحه اول مقاله
The putative penicillin-binding proteins 1 and 2 are important for viability, growth and cell morphology of Brucella melitensis
چکیده انگلیسی

The penicillin-binding proteins (PBPs) are enzymes that regulate the assembly of the peptidoglycan layer of the bacterial cell wall. The genome of Brucella melitensis strain 16 M possesses seven pbp genes: three in pbp-1 family (designated as 1A, 1B, and 1C); one in pbp-2 family; and three in pbp-6 family (designated as 6A, 6B, and 6C). We investigated the importance of pbp-1 and pbp-2 genes to viability, cell morphology and infectivity of B. melitensis. A recombinant B. melitensis strain (designated 16 MΔpbp1C) was generated by disrupting the pbp-1C of strain 16 M by allelic exchange. This strain produced nearly 20% smaller colonies on trypticase soy agar plates, and grew slower in trypticase soy broth compared to the strain 16 M. Electron microscopy revealed that strain 16 M exhibited native cocco-bacillus morphology, while 16 MΔpbp1C possessed a spherical morphology. Strain 16 MΔpbp1C did not differ from strain 16 M in terms of recovery from infected mouse macrophage cell line J774.1, or recovery from spleens of infected BALB/c mice, suggesting that pbp-1C is dispensable for intracellular persistence of B. melitensis. Expression of mRNA of fixR, the gene downstream of pbp-1C was similar between the strains 16 M and 16 MΔpbp1C suggesting that disruption of pbp-1C did not induce any polar effects. Multiple attempts to mutate pbp-1A, pbp-1B, or pbp-2 genes failed, most probably because these genes are indispensable for viability of B. melitensis. Our findings suggest that pbp-1C regulates in vitro growth and cell morphology, whereas pbp-1A, pbp-1B, and pbp-2 are essential for viability of B. melitensis.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Veterinary Microbiology - Volume 133, Issue 4, 2 February 2009, Pages 387–393
نویسندگان
, , , , ,