scholarly journals Transcriptional Expression of the ompA, cpaf, tarp, and tox Genes of Chlamydia trachomatis Clinical Isolates at Different Stages of the Developmental Cycle

2019 ◽  
Vol 7 (6) ◽  
pp. 153 ◽  
Author(s):  
Suvi Korhonen ◽  
Kati Hokynar ◽  
Laura Mannonen ◽  
Jorma Paavonen ◽  
Eija Hiltunen-Back ◽  
...  
Keyword(s):  
Gene Expression ◽  
Chlamydia Trachomatis ◽  
Cultured Cells ◽  
Expression Patterns ◽  
Clinical Isolates ◽  
Gene Expression Patterns ◽  
Developmental Cycle ◽  
Passage Number ◽  
Low Passage ◽  
Reference Strains

The transcriptional gene expression patterns of Chlamydia trachomatis have mainly been studied using reference strains propagated in cultured cells. Here, using five low-passage-number C. trachomatis clinical isolates that originated from asymptomatic or symptomatic female patients, the in vitro expression of the ompA, cpaf, tarp, and tox genes was studied with reverse transcriptase real-time PCR during the chlamydial developmental cycle. We observed dissimilarities in the gene expression patterns between the low-passage-number clinical isolates and the reference strains. The expression of ompA and the peak of the tox expression were observed earlier in the reference strains than in most of the clinical isolates. The expression of cpaf was high in the reference strains compared with the clinical isolates at the mid-phase (6–24 hours post infection) of the developmental cycle. All of the strains had a rather similar tarp expression profile. Four out of five clinical isolates exhibited slower growth kinetics compared with the reference strains. The use of low-passage-number C. trachomatis clinical isolates instead of reference strains in the studies might better reflect the situation in human infection.

scholarly journals Differential expression of groEL-1, incB, pyk-F, tal, hctA and omcB genes during Chlamydia trachomatis developmental cycle

PLoS ONE ◽  
2021 ◽  
Vol 16 (4) ◽  
pp. e0249358
Author(s):  
Gugulethu F. Mzobe ◽  
Sinaye Ngcapu ◽  
Bronwyn C. Joubert ◽  
Willem A. Sturm
Keyword(s):  
Gene Expression ◽  
Chlamydia Trachomatis ◽  
Cell Line ◽  
Cell Lines ◽  
Growth Kinetics ◽  
Reference Strain ◽  
Expression Patterns ◽  
Clinical Isolates ◽  
Gene Expression Patterns ◽  
Developmental Cycle

Chlamydia trachomatis infects squamous and columnar epithelia at the mucosal surface. Research on gene expression patterns of C. trachomatis has predominantly focused on non-native host cells, with limited data on growth kinetics and gene expression of chlamydia in keratinocytes. Here, we investigated whether early, mid, and late chlamydial genes observed in HeLa cell line studies were co-ordinately regulated at the transcriptional level even in the keratinized cell line model and whether the expression was stage-specific during the developmental cycle. HaCaT cell lines were infected with chlamydia clinical isolates (US151and serovar E) and reference strain (L2 434). Expression of groEL-1, incB, pyk-F, tal, hctA, and omcB genes was conducted with comparative real-time PCR and transcriptional events during the chlamydial developmental cycle using transmission electron microscopy. The relative expression level of each gene and fold difference were calculated using the 2-ΔΔCT method. The expression of groEL-1 and pyk-F genes was highest at 2 hours post-infection (hpi) in the L2 434 and serovar E. The expression of incB gene increased at 2 hpi in L2 434 and serovar E but peaked at 12 hpi in serovar E. L2 434 and US151 had similar tal expression profiles. Increased expression of hctA and omcB genes were found at 2 and 36 hpi in L2 434. Both clinical isolates and reference strains presented the normal chlamydial replication cycle comprising elementary bodies and reticulate bodies within 36 hpi. We show different gene expression patterns between clinical isolates and reference strain during in vitro infection of keratinocytes, with reference strain-inducing consistent expression of genes. These findings confirm that keratinocytes are appropriate cell lines to interrogate cell differentiation, growth kinetics, and gene expression of C. trachomatis infection. Furthermore, more studies with different clinical isolates and genes are needed to better understand the Chlamydial pathogenesis in keratinocytes.

scholarly journals CadA Negatively Regulates Escherichia coli O157:H7 Adherence and Intestinal Colonization

2008 ◽  
Vol 76 (11) ◽  
pp. 5072-5081 ◽  
Author(s):  
Roberto C. Vazquez-Juarez ◽  
Jeeba A. Kuriakose ◽  
David A. Rasko ◽  
Jennifer M. Ritchie ◽  
Melissa M. Kendall ◽  
...  
Keyword(s):  
Gene Expression ◽  
Escherichia Coli ◽  
Type Strain ◽  
Wild Type Strain ◽  
Cultured Cells ◽  
Expression Patterns ◽  
Gene Array ◽  
Rabbit Model ◽  
Gene Expression Patterns ◽  
Wild Type

ABSTRACT Adherence of pathogenic Escherichia coli strains to intestinal epithelia is essential for infection. For enterohemorrhagic E. coli (EHEC) serotype O157:H7, we have previously demonstrated that multiple factors govern this pathogen's adherence to HeLa cells (A. G. Torres and J. B. Kaper, Infect. Immun. 71:4985-4995, 2003). One of these factors is CadA, a lysine decarboxylase, and this protein has been proposed to negatively regulate virulence in several enteric pathogens. In the case of EHEC strains, CadA modulates expression of the intimin, an outer membrane adhesin involved in pathogenesis. Here, we inactivated cadA in O157:H7 strain 86-24 to investigate the role of this gene in EHEC adhesion to tissue-cultured monolayers, global gene expression patterns, and colonization of the infant rabbit intestine. The cadA mutant did not possess lysine decarboxylation activity and was hyperadherent to tissue-cultured cells. Adherence of the cadA mutant was nearly twofold greater than that of the wild type, and the adherence phenotype was independent of pH, lysine, or cadaverine in the media. Additionally, complementation of the cadA defect reduced adherence back to wild-type levels, and it was found that the mutation affected the expression of the intimin protein. Disruption of the eae gene (intimin-encoding gene) in the cadA mutant significantly reduced its adherence to tissue-cultured cells. However, adherence of the cadA eae double mutant was greater than that of an 86-24 eae mutant, suggesting that the enhanced adherence of the cadA mutant is not entirely attributable to enhanced expression of intimin in this background. Gene array analysis revealed that the cadA mutation significantly altered EHEC gene expression patterns; expression of 1,332 genes was downregulated and that of 132 genes was upregulated in the mutant compared to the wild-type strain. Interestingly, the gene expression variation shows an EHEC-biased gene alteration including intergenic regions. Two putative adhesins, flagella and F9 fimbria, were upregulated in the cadA mutant, suggestive of their association with adherence in the absence of the Cad regulatory mechanism. In the infant rabbit model, the cadA mutant outcompeted the wild-type strain in the ileum but not in the cecum or mid-colon, raising the possibility that CadA negatively regulates EHEC pathogenicity in a tissue-specific fashion.

Gene expression patterns in blood predict future severe endpoints in community acquired pneumonia

Pneumologie ◽  
2018 ◽  
Vol 72 (S 01) ◽  
pp. S8-S9
Author(s):  
M Bauer ◽  
H Kirsten ◽  
E Grunow ◽  
P Ahnert ◽  
M Kiehntopf ◽  
...  
Keyword(s):  
Gene Expression ◽  
Expression Patterns ◽  
Community Acquired Pneumonia ◽  
Gene Expression Patterns
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