scholarly journals Antimicrobial Compounds Produced by Vaginal Lactobacillus crispatus Are Able to Strongly Inhibit Candida albicans Growth, Hyphal Formation and Regulate Virulence-related Gene Expressions

2017 ◽  
Vol 08 ◽  
Author(s):  
Shuai Wang ◽  
Qiangyi Wang ◽  
Ence Yang ◽  
Ling Yan ◽  
Tong Li ◽  
...  
Author(s):  
Yu-De Song ◽  
Chih-Chieh Hsu ◽  
Shi Qian Lew ◽  
Ching-Hsuan Lin

Abstract NDT80-like family genes are highly conserved across a large group of fungi, but the functions of each Ndt80 protein are diverse and have evolved differently among yeasts and pathogens. The unique NDT80 gene in budding yeast is required for sexual reproduction, whereas three NDT80-like genes, namely, NDT80, REP1, and RON1, found in Candida albicans exhibit distinct functions. Notably, it was suggested that REP1, rather than RON1, is required for N-acetylglucosamine (GlcNAc) catabolism. Although Candida tropicalis, a widely dispersed fungal pathogen in tropical and subtropical areas, is closely related to Candida albicans, its phenotypic, pathogenic and environmental adaptation characteristics are remarkably divergent. In this study, we focused on the Ron1 transcription factor in C. tropicalis. Protein alignment showed that C. tropicalis Ron1 (CtRon1) shares 39.7% identity with C. albicans Ron1 (CaRon1). Compared to the wild-type strain, the C. tropicalis ron1Δ strains exhibited normal growth in different carbon sources and had similar expression levels of several GlcNAc catabolic genes during GlcNAc treatment. In contrast, C. tropicalis REP1 is responsible for GlcNAc catabolism and is involved in GlcNAc catabolic gene expressions, similar to C. albicans Rep1. However, REP1 deletion strains in C. tropicalis promote hyphal development in GlcNAc with low glucose content. Interestingly, CtRON1, but not CaRON1, deletion mutants exhibited significantly impaired hyphal growth and biofilm formation. As expected, CtRON1 was required for full virulence. Together, the results of this study showed divergent functions of CtRon1 compared to CaRon1; CtRon1 plays a key role in yeast-hyphal dimorphism, biofilm formation and virulence. Lay Abstract In this study, we identified the role of RON1, an NDT80-like gene, in Candida tropicalis. Unlike the gene in Candida albicans, our studies showed that RON1 is a key regulator of hyphal formation, biofilm development and virulence but is dispensable for N-acetylglucosamine catabolism in C. tropicalis.


2011 ◽  
Vol 107 (8) ◽  
pp. 1112-1118 ◽  
Author(s):  
Pei-Hsuan Tsai ◽  
Jun-Jen Liu ◽  
Chui-Li Yeh ◽  
Wan-Chun Chiu ◽  
Sung-Ling Yeh

There are close links among hyperglycaemia, oxidative stress and diabetic complications. Glutamine (GLN) is an amino acid with immunomodulatory properties. The present study investigated the effect of dietary GLN on oxidative stress-relative gene expressions and tissue oxidative damage in diabetes. There were one normal control (NC) and two diabetic groups in the present study. Diabetes was induced by an intraperitoneal injection of nicotinamide followed by streptozotocin (STZ). Rats in the NC group were fed a regular chow diet. In the two diabetic groups, one group (diabetes mellitus, DM) was fed a common semi-purified diet while the other group received a diet in which part of the casein was replaced by GLN (DM-GLN). GLN provided 25 % of total amino acid N. The experimental groups were fed the respective diets for 8 weeks, and then the rats were killed for further analysis. The results showed that blood thioredoxin-interacting protein (Txnip) mRNA expression in the diabetic groups was higher than that in the NC group. Compared with the DM group, the DM-GLN group had lower glutamine fructose-6-phosphate transaminase 1, a receptor of advanced glycation end products, and Txnip gene expressions in blood mononuclear cells. The total antioxidant capacity was lower and antioxidant enzyme activities were altered by the diabetic condition. GLN supplementation increased antioxidant capacity and normalised antioxidant enzyme activities. Also, the renal nitrotyrosine level and Txnip mRNA expression were lower when GLN was administered. These results suggest that dietary GLN supplementation decreases oxidative stress-related gene expression, increases the antioxidant potential and may consequently attenuate renal oxidative damage in rats with STZ-induced diabetes.


2017 ◽  
Vol 130 (3) ◽  
pp. 273-279 ◽  
Author(s):  
Xiao-Xi Niu ◽  
Ting Li ◽  
Xu Zhang ◽  
Su-Xia Wang ◽  
Zhao-Hui Liu

2021 ◽  
Author(s):  
Yan Ma ◽  
Minhua Xu ◽  
Hancong Liu ◽  
Tiantian Yu ◽  
Ping Guo ◽  
...  

Abstract Background: As we all know, bacterial and fungal infections have become one of the threats to human health. Microbial secondary metabolites are one of the main sources of bioactive natural products. It is estimated that around 60% of all foregone antibiotics are derived from secondary metabolites produced by filamentous actinomycete bacteria. Gordonia spp. are members of the actinomycete family, their contribution to the environment improvement and environmental protection by their biological degradation ability, but there are few studies on their antimicrobial activity of their secondary metabolites. Our team isolated a Gordonia strain WA 4-31 with anti-Candida albicans activity from the intestinal tract of Periplaneta americana in the early stage.Results: In this study, we firstly identified the strain WA 4-31 by the morphological characteristics and the phylogenetic analyses, and found that it homologous to a strain of Gordonia from the Indian desert (EU333873) by 100%. Then four compounds, Actinomycin D (1), Actinomycin X2 (2), Mojavensin A (3) and cyclic (leucine-leucne) dipeptide (4) were purified from the EtOH extract of the fermented broth of the strain. The compounds 1-4 had activities against Candida albicans, Aspergillus niger, Aspergillus fumigatus and Trichophyton rubrum. They also had activities against MRSA, S.aureus, K.peneumoniae and E.coli in different degree. The minimum inhibitory concentration of Actinomycin D and Actinomycin X2 on MASA was 0.25 μg/mL. Interestingly, we found that when Mojavensin A was mixed with compound 4 ratio of 1:1, the solution of the compounds was better than the single on anti-Candida albicans. Besides, compounds 1-3 had varying degrees of cytotoxicity on CNE-2 cells and HepG-2 cells.Conclusions: The present study firstly reported the antimicrobial compounds isolated from Gordonia. These indicated that rare actinomycetes from the intestinal tract of Periplaneta americana possessed a potential as a source of active secondary metabolites.


2020 ◽  
Vol 8 (11) ◽  
pp. 1771
Author(s):  
Akshaya Lakshmi Krishnamoorthy ◽  
Alex A. Lemus ◽  
Adline Princy Solomon ◽  
Alex M. Valm ◽  
Prasanna Neelakantan

Candida albicans as an opportunistic pathogen exploits the host immune system and causes a variety of life-threatening infections. The polymorphic nature of this fungus gives it tremendous advantage to breach mucosal barriers and cause oral and disseminated infections. Similar to C. albicans, Enterococcus faecalis is a major opportunistic pathogen, which is of critical concern in immunocompromised patients. There is increasing evidence that E. faecalis co-exists with C. albicans in the human body in disease samples. While the interactive profiles between these two organisms have been studied on abiotic substrates and mouse models, studies on their interactions on human oral mucosal surfaces are non-existent. Here, for the first time, we comprehensively characterized the interactive profiles between laboratory and clinical isolates of C. albicans (SC5314 and BF1) and E. faecalis (OG1RF and P52S) on an organotypic oral mucosal model. Our results demonstrated that the dual species biofilms resulted in profound surface erosion and significantly increased microbial invasion into mucosal compartments, compared to either species alone. Notably, several genes of C. albicans involved in tissue adhesion, hyphal formation, fungal invasion, and biofilm formation were significantly upregulated in the presence of E. faecalis. By contrast, E. faecalis genes involved in quorum sensing, biofilm formation, virulence, and mammalian cell invasion were downregulated. This study highlights the synergistic cross-kingdom interactions between E. faecalis and C. albicans in mucosal tissue invasion.


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