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GAPDH, rhbC, and vapA gene expression in Rhodococcus equi cultured under different iron concentrations.
- Source :
-
Microbial pathogenesis [Microb Pathog] 2020 Feb; Vol. 139, pp. 103885. Date of Electronic Publication: 2019 Nov 29. - Publication Year :
- 2020
-
Abstract
- The ability of Rhodococcus equi to survive in macrophages and cause pneumonia in foals depends on vapA and rhbC genes, which produce the virulence-associated protein A (VapA) and the rhequichelin siderophore, respectively. Virulent R. equi acquires Fe from transferrin by unknown mechanisms. Our objectives were to determine the role of GAPDH in Fe homeostasis, to further characterize GAPDH, rhbC, and vapA expression under iron homeostasis, and to document the occurrence of rhbC gene in R. equi isolates. Therefore, vapA + R. equi was cultured under excessive, physiologic, and restricted iron concentrations, and quantitative culture and gene expression were performed. The relative expression of GAPDH, rhbC, and vapA after 48 h of culture were analyzed by qPCR. To determine the rhbC occurrence, total DNA was extracted from R. equi isolated from foals with clinical rhodococcosis (n = 22), healthy horses (feces, n = 16; nasal swab, n = 9), soil (n = 6), and 2 ATCC reference strains. Conventional PCR was performed to identify genus/species, vapA, and rhbC genes. Iron restriction proportionally decreased R. equi growth rates, and induced high expression of both GAPDH and vapA. The putative role of GAPDH in R. equi iron homeostasis should be further investigated. rhbC was significantly up-regulated under both Fe excess and critical starvation. The rhbC gene was identified in all clinical isolates and soil, but it was absent in 2 isolates from healthy horses, suggesting that rhequichelin is not required for R. equi nasal and intestinal colonization.<br />Competing Interests: Declaration of competing interest None.<br /> (Copyright © 2019 Elsevier Ltd. All rights reserved.)
- Subjects :
- Homeostasis
Rhodococcus equi growth & development
Virulence genetics
Virulence Factors genetics
Actinomycetales Infections microbiology
Bacterial Proteins genetics
Gene Expression Regulation, Bacterial
Glyceraldehyde-3-Phosphate Dehydrogenase (Phosphorylating) genetics
Iron metabolism
Rhodococcus equi genetics
Rhodococcus equi metabolism
Subjects
Details
- Language :
- English
- ISSN :
- 1096-1208
- Volume :
- 139
- Database :
- MEDLINE
- Journal :
- Microbial pathogenesis
- Publication Type :
- Academic Journal
- Accession number :
- 31790793
- Full Text :
- https://doi.org/10.1016/j.micpath.2019.103885