• Journal of Microbiology and Biotechnology
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• v.22 no.12
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• pp.1644-1652
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• 2012

Iron plays a key role in host-pathogen interactions. Microbial pathogens require iron for survival and virulence, whereas mammalian hosts sequester and withhold iron as a means of nutritional immunity. We previously identified two paralogous genes, CFT1 and CFT2, which encode homologs of a fungal iron permease, Cft1 and Cft2, respectively, in the human fungal pathogen Cryptococcus neoformans. Cft1 was shown to play a role in the high-affinity reductive iron uptake system, and was required for transferrin utilization and full virulence in mammalian hosts. However, no role of Cft2 has been suggested yet. Here, we identified the third gene, CFT3, that produces an additional fungal iron permease homolog in C. neoformans, and we also generated the cft3 mutant for functional characterization. We aimed to reveal distinct functions of Cft1, Cft2 and Cft3 by analyzing phenotypes of the mutants lacking CFT1, CFT2 and CFT3, respectively. The endogenous promoter of CFT1, CFT2 and CFT3 was replaced with the inducible GAL7 promoter in the wild-type strain or in the cft1 mutant for gain-of-function analysis. Using these strains, we were able to find that CFT2 is required for growth in low-iron conditions in the absence of CFT1 and that overexpression of CFT2 compensates for deficiency of the cft1 mutant in iron uptake and various cellular stress conditions. However, unlike CFT2, no clear phenotypic characteristic of the cft3 mutant and the strain overexpressing CFT3 was observed. Overall, our data suggested a redundant role of Cft2 in the high-affinity iron uptake and stress responses in C. neoformans.

• Journal of Animal Science and Technology
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• v.63 no.6
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• pp.1423-1432
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• 2021

To elucidate the role and mechanism of microbes, we combined culture-dependent and culture-independent approaches to investigate differences in gut bacterial composition between sows and weaned pigs. Under anaerobic conditions, several nonselective and selective media were used for isolation from fecal samples. All isolated bacteria were identified and classified through 16S rRNA sequencing, and the microbiota composition of the fecal samples was analyzed by metagenomics using next generation sequencing (NGS) technology. A total of 278 and 149 colonies were acquired from the sow and weaned pig fecal samples, respectively. Culturomics analysis revealed that diverse bacterial genus and species belonged to Firmicutes, Actinobacteria, Proteobacteria, and Bacteroidetes were isolated from sow and weaned pigs. When comparing culture-dependent and culture-independent analyses, 191 bacterial species and 2 archaeal bacterial species were detected through culture-independent analysis, and a total of 23 bacteria were isolated through a culture-dependent approach, of which 65% were not detected by metagenomics. In conclusion, culturomics and metagenomics should be properly combined to fully understand the intestinal microbiota, and livestock-derived microbial resources should be informed by culturomic approaches to understand and utilize the mechanism of host-microbe interactions.

• The Plant Pathology Journal
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• v.38 no.1
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• pp.1-11
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• 2022

Fusarium culmorum is one of the most important causal agents of root rot of wheat. In this study, 10 F. culmorum isolates were collected from farms located in five agro-ecological regions of Morocco. These were used to challenge 20 durum wheat genotypes via artificial inoculation of plant roots under controlled conditions. The isolate virulence was determined by three traits (roots browning index, stem browning index, and severity of root rot). An alpha-lattice design with three replicates was used, and the resulting ANOVA revealed a significant (P < 0.01) effect of isolate (I), genotype (G), and G × I interaction. A total of four response types were observed (R, MR, MS, and S) revealing that different genes in both the pathogen and the host were activated in 53% of interactions. Most genotypes were susceptible to eight or more isolates, while the Moroccan cultivar Marouan was reported resistant to three isolates and moderately resistant to three others. Similarly, the Australian breeding line SSD1479-117 was reported resistant to two isolates and moderately resistant to four others. The ICARDA elites Icaverve, Berghisyr, Berghisyr2, Amina, and Icaverve2 were identified as moderately resistant. Principal component analysis based on the genotypes responses defined two major clusters and two sub-clusters for the 10 F. culmorum isolates. Isolate Fc9 collected in Khemis Zemamra was the most virulent while isolate Fc3 collected in Haj-Kaddour was the least virulent. This work provides initial results for the discovery of differential reactions between the durum lines and isolates and the identification of novel sources of resistance.

• Journal of dental hygiene science
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• v.14 no.4
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• pp.477-487
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• 2014

Of the many pathogenic Candida species, Candida albicans is the main fungal pathogen of humans. The oral environmental factors considered in the Candida albicans colony forming unit test contain both host and microbial factors associated with candidiasis. In particular, Candida biofilms can develop on surfaces of prosthesis. The purpose of this study was to investigate the distribution of oral Candida species between the type of prosthesis and the situation of oral environment in patient with prosthetic appliance. The patients were 30 elderly subjects with different types of prosthesis, 7 who wore denture, 12 who wore implant and 15 who wore removable orthodontic appliance. We used Candida albicans colony forming unit test using saliva to exam the distribution of Candida albicans related with 5 oral environmental factors, gender, smoking or nonsmoking, alcohol/nonalcohol consumption, the type of prosthetic appliance and its treatment duration as well as tooth brushing frequency per day. In conclusion, for the patient's gender, site in the oral cavity and the type of prosthetic appliance and its treatment duration was associated with an increase in the distribution of Candida albicans in saliva. The distribution of Candida albicans within the oral cavity performs to be modulated to varying extents by oral environmental factors and, further investigations are required to elucidate these complex interactions.