scholarly journals The microbial ecology of Candida albicans strains CHN1 and SC5314 in mice

2021 ◽  
Vol 3 (12) ◽  
Author(s):  
Malak Bazzi ◽  
Katie Nawrocki ◽  
Christopher Brown ◽  
Nicole Falkowski ◽  
Kelsey Stark ◽  
...  

Strain SC5314 is the most widely studied strain of Candida albicans. Despite C. albicans being the most commonly isolated yeast from the human gastrointestinal (GI) microbiome, strain SC5314 does not stably colonize the mouse GI tract long term, even after antibiotic disruption. In contrast, strain CHN1 will stably colonize the mouse GI tract long term. Comparative genomic analysis of strain CHN1 indicates that it belongs to a different evolutionary clade of C. albicans than strain SC5314. Previous studies from our laboratory have shown that colonization by strain CHN1 causes a change in the GI bacterial microbiome of mice and predisposes them to more robust Th2 immune responses. Despite this, little is known about the GI microbial ecology of SC5314 vs. CHN1 and subsequent host responses. Using a short-term antibiotic disruption model in C57BL/6 mice, we have been able to observe significantly different colonization kinetics between these two C. albicans strains, with CHN1 establishing stable long-term colonization. In contrast, colonization by SC5314 was lower, highly variable and cage-dependent. C. albicans colonization kinetics impacted the composition of the bacterial microbiome with a marked effect on the levels of Lactobacillus and Enterococcus. qPCR analysis of 46 host immune response genes did not detect significant differences in host gene expression between SC5134 and CHN1 colonized mice, except for chitinase expression. Thus, these studies suggest that yeast-bacteria interactions in the microbiome may be far more important in determining long-term colonization potential of C. albicans and secondary immunomodulatory effects.

2019 ◽  
Author(s):  
Yi-Lung Chen ◽  
Sean Ting-Shyang Wei ◽  
Yin-Ru Chiang

AbstractSteroid hormones (androgens and estrogens) are crucial for development, reproduction, and communication of multicellular eukaryotes. The ubiquitous distribution and persistence of steroid hormones in our ecosystems have become an environmental issue due to the adverse effects on wildlife and humans upon long-term exposure. Microbial degradation is critical for the removal of steroid hormones from ecosystems. The aerobic degradation pathways for androgens and estrogens and the anaerobic degradation pathway for androgen have been studied into some details; however, the mechanism for anaerobic estrogen degradation remains completely unknown. Here, we presented the circular genomes of D. oestradiolicum DSM 16959 and Denitratisoma sp. strain DHT3, two betaproteobacteria capable of anaerobic estrogen degradation. We identified the genes involved in steroid transformation and in the anaerobic 2,3-seco pathway in both genomes. Additionally, the comparative genomic analysis revealed that genes exclusively represented in estrogen-degrading anaerobes might play a role in anaerobic estrogen catabolism.


2012 ◽  
Vol 80 (10) ◽  
pp. 3371-3380 ◽  
Author(s):  
Katie L. Mason ◽  
John R. Erb Downward ◽  
Kelly D. Mason ◽  
Nicole R. Falkowski ◽  
Kathryn A. Eaton ◽  
...  

ABSTRACTCandida albicansis a normal member of the gastrointestinal (GI) tract microbiota of healthy humans, but during host immunosuppression or alterations in the bacterial microbiota,C. albicanscan disseminate and cause life-threatening illness. The bacterial microbiome of the GI tract, including lactic acid bacteria (LAB), plays a vital role in preventing fungal invasion. However, little is known about the role ofC. albicansin shaping the bacterial microbiota during antibiotic recovery. We investigated the fungal burdens in the GI tracts of germfree mice and mice with a disturbed microbiome to demonstrate the role of the microbiota in preventingC. albicanscolonization. Histological analysis demonstrated that colonization withC. albicansduring antibiotic treatment does not trigger overt inflammation in the murine cecum. Bacterial diversity is reduced long term following cefoperazone treatment, but the presence ofC. albicansduring antibiotic recovery promoted the recovery of bacterial diversity. Cefoperazone diminishesBacteroidetespopulations long term in the ceca of mice, but the presence ofC. albicansduring cefoperazone recovery promotedBacteroidetespopulation recovery. However, the presence ofC. albicansresulted in a long-term reduction inLactobacillusspp. and promotedEnterococcus faecalispopulations. Previous studies have focused on the ability of bacteria to alterC. albicans; this study addresses the ability ofC. albicansto alter the bacterial microbiota during nonpathogenic colonization.


Author(s):  
Karen D. Zeise ◽  
Robert J. Woods ◽  
Gary B. Huffnagle

Emerging studies have highlighted the disproportionate role of Candida albicans in influencing both early community assembly of the bacterial microbiome and dysbiosis during allergic diseases and intestinal inflammation. Nonpathogenic colonization of the human gastrointestinal (GI) tract by C. albicans is common, and the role of this single fungal species in modulating bacterial community reassembly after broad-spectrum antibiotics can be readily recapitulated in mouse studies.


2018 ◽  
Vol 6 (5) ◽  
Author(s):  
Thais Fernanda Bartelli ◽  
Danielle do Carmo Ferreira Bruno ◽  
Marcelo R. S. Briones

ABSTRACT The genetic variability of the opportunistic pathogen Candida albicans is an important adaptive mechanism. Here, we present the whole-genome sequences of the C. albicans SC5314 strain under two different growth conditions, providing useful information for comparative genomic studies and further intraspecific analysis.


Genes ◽  
2020 ◽  
Vol 11 (9) ◽  
pp. 1025
Author(s):  
Shaohua Zhao ◽  
Cong Li ◽  
Chih-Hao Hsu ◽  
Gregory H. Tyson ◽  
Errol Strain ◽  
...  

Salmonella is a leading cause of bacterial infections in animals and humans. We sequenced a collection of 450 Salmonella strains from diseased animals to better understand the genetic makeup of their virulence and resistance features. The presence of Salmonella pathogenicity islands (SPIs) varied by serotype. S. Enteritidis carried the most SPIs (n = 15), while S. Mbandaka, S. Cerro, S. Meleagridis, and S. Havana carried the least (n = 10). S. Typhimurium, S. Choleraesuis, S. I 4,5,12:i:-, and S. Enteritidis each contained the spv operon on IncFII or IncFII-IncFIB hybrid plasmids. Two S. IIIa carried a spv operon with spvD deletion on the chromosome. Twelve plasmid types including 24 hybrid plasmids were identified. IncA/C was frequently associated with S. Newport (83%) and S. Agona (100%) from bovine, whereas IncFII (100%), IncFIB (100%), and IncQ1 (94%) were seen in S. Choleraesuis from swine. IncX (100%) was detected in all S. Kentucky from chicken. A total of 60 antimicrobial resistance genes (ARGs), four disinfectant resistances genes (DRGs) and 33 heavy metal resistance genes (HMRGs) were identified. The Salmonella strains from sick animals contained various SPIs, resistance genes and plasmid types based on the serotype and source of the isolates. Such complicated genomic structures shed light on the strain characteristics contributing to the severity of disease and treatment failures in Salmonella infections, including those causing illnesses in animals.


2021 ◽  
Vol 9 (2) ◽  
pp. 348
Author(s):  
Florian Tagini ◽  
Trestan Pillonel ◽  
Claire Bertelli ◽  
Katia Jaton ◽  
Gilbert Greub

The Mycobacterium kansasii species comprises six subtypes that were recently classified into six closely related species; Mycobacterium kansasii (formerly M. kansasii subtype 1), Mycobacterium persicum (subtype 2), Mycobacterium pseudokansasii (subtype 3), Mycobacterium ostraviense (subtype 4), Mycobacterium innocens (subtype 5) and Mycobacterium attenuatum (subtype 6). Together with Mycobacterium gastri, they form the M. kansasii complex. M. kansasii is the most frequent and most pathogenic species of the complex. M. persicum is classically associated with diseases in immunosuppressed patients, and the other species are mostly colonizers, and are only very rarely reported in ill patients. Comparative genomics was used to assess the genetic determinants leading to the pathogenicity of members of the M. kansasii complex. The genomes of 51 isolates collected from patients with and without disease were sequenced and compared with 24 publicly available genomes. The pathogenicity of each isolate was determined based on the clinical records or public metadata. A comparative genomic analysis showed that all M. persicum, M. ostraviense, M innocens and M. gastri isolates lacked the ESX-1-associated EspACD locus that is thought to play a crucial role in the pathogenicity of M. tuberculosis and other non-tuberculous mycobacteria. Furthermore, M. kansasii was the only species exhibiting a 25-Kb-large genomic island encoding for 17 type-VII secretion system-associated proteins. Finally, a genome-wide association analysis revealed that two consecutive genes encoding a hemerythrin-like protein and a nitroreductase-like protein were significantly associated with pathogenicity. These two genes may be involved in the resistance to reactive oxygen and nitrogen species, a required mechanism for the intracellular survival of bacteria. Three non-pathogenic M. kansasii lacked these genes likely due to two distinct distributive conjugal transfers (DCTs) between M. attenuatum and M. kansasii, and one DCT between M. persicum and M. kansasii. To our knowledge, this is the first study linking DCT to reduced pathogenicity.


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