Results: 9

An investigation of virulence factors of Legionella pneumophila environmental isolates

Braz. j. microbiol; 49 (1), 2018
ABSTRACT Nine Legionella pneumophila strains isolated from cooling towers and a standard strain (L. pneumophila serogroup 1, ATCC 33152, Philadelphia 1) were analyzed and compared in terms of motility, flagella structure, ability to form biofilms, enzymatic activities (hemolysin, nucleases, protease, pho...

Gain of function in Mycobacterium bovis BCG Moreau due to loss of a transcriptional repressor

Mem. Inst. Oswaldo Cruz; 113 (11), 2018
The Bacille Calmette-Guérin (BCG) vaccine comprises a family of genetically different strains derived by the loss of genomic regions (RDs) and other mutations. In BCG Moreau, loss of RD16 inactivates rv3405c * , encoding a transcriptional repressor that negatively regulates the expression of Rv3406, an...

Construction of Mycobacterium tuberculosis cdd knockout and evaluation of invasion and growth in macrophages

Mem. Inst. Oswaldo Cruz; 112 (11), 2017
Cytidine deaminase (MtCDA), encoded by cdd gene (Rv3315c), is the only enzyme identified in nucleotide biosynthesis pathway of Mycobacterium tuberculosis that is able to recycle cytidine and deoxycytidine. An M. tuberculosis knockout strain for cdd gene was obtained by allelic replacement. Evaluation of ...

IL-10 down-regulates the expression of survival associated gene hspX of Mycobacterium tuberculosis in murine macrophage

Braz. j. infect. dis; 21 (4), 2017
Abstract Mycobacterium tuberculosis (MTB) adopts a special survival strategy to overcome the killing mechanism(s) of host immune system. Amongst the many known factors, small heat shock protein 16.3 (sHSP16.3) of MTB encoded by gene hspX has been reported to be critical for the survival of MTB. In the pr...

Characterisation of iunH gene knockout strain from Mycobacterium tuberculosis

Mem. Inst. Oswaldo Cruz; 112 (3), 2017
BACKGROUND Tuberculosis (TB) is an infectious disease caused mainly by the bacillus Mycobacterium tuberculosis. The better understanding of important metabolic pathways from M. tuberculosis can contribute to the development of novel therapeutic and prophylactic strategies to combat TB. Nucleoside hydrol...

Differential roles for pathogenicity islands SPI-13 and SPI-8 in the interaction of Salmonella Enteritidis and Salmonella Typhi with murine and human macrophages

Biol. Res; 50 (), 2017
BACKGROUND: Salmonella pathogenicity island (SPI)-13 is conserved in many serovars of S. enterica, including S. Enteritidis, S. Typhimurium and S. Gallinarum. However, it is absent in typhoid serovars such as S. Typhi and Paratyphi A, which carry SPI-8 at the same genomic location. Because the interactio...

Estudo da capacidade fagocítica de macrófagos humanos frente a diferentes cepas de Enterococcus faecalis

Enterococcus faecalis (E. faecalis) é um microrganismo presente em lesões endodônticas persistentes, mostrando maior resistência do que outras bactérias ao Hidróxido de Cálcio, um medicamento alcalino que consegue eliminar diversos microrganismos durante o tratamento endodôntico. Assim, os...

stg fimbrial operon from S. Typhi STH2370 contributes to association and cell disruption of epithelial and macrophage-like cells

Biol. Res; 48 (), 2015
BACKGROUND: Salmonella enterica serovar Typhi (S. Typhi) stg operon, encoding a chaperone/usher fimbria (CU), contributes to an increased adherence to human epithelial cells. However, one report suggests that the presence of the Stg fimbria impairs the monocyte-bacteria association, as deduced by the low...

Normalization of the levels of inflammatory molecules in Mycobacterium smegmatis-infected U937 cells by fibrate pretreatment

Biol. Res; 47 (), 2014
BACKGROUND: Tuberculosis (TB) is a respiratory tract disease caused by Mycobacterium tuberculosis infection. M. tuberculosis exploits immune privilege to grow and divide in pleural macrophages. Fibrates are associated with the immune response and control lipid metabolism through glycolysis with β-oxidat...