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Non-albicans Candida species and other rare yeasts have emerged as major opportunistic pathogens in fungal infections. Identification of opportunistic yeasts in developing countries is mainly performed by phenotypic assay, which are time-consuming and prone to errors. The aim of the present study was to evaluate PCR-RFLP as a routinely used identification technique for the most clinically important Candida species in Iran and make a comparison with a novel multiplex PCR, called 21-plex PCR. One hundred and seventy-three yeast isolates from clinical sources were selected and identified with sequence analysis of the D1/D2 domains of rDNA (LSU rDNA) sequencing as the gold standard method. The results were compared with those obtained by PCR-RFLP using MspI restriction enzyme and the 21-plex PCR. PCR-RFLP correctly identified 93.4% of common pathogenic Candida species (C. albicans, C. glabrata, C. parapsilosis, C. tropicalis, and P. kudriavsevii (=?C. krusei)) and was able to identify 45.5% of isolates of the uncommon yeast species compared to the D1/D2 rDNA sequencing. Compared with PCR-RFLP, all common Candida species and 72.7% of uncommon yeast species were correctly identified by the 21-plex PCR. The application of the 21-plex PCR assay as a non-sequence-based molecular method for the identification of common and rare yeasts can reduce turnaround time and costs for the identification of clinically important yeasts and can be applied in resource-limited settings.
相似文献The development of salt‐tolerant genotypes is key to a better utilization of salinized irrigated lands. Given the relatively low genetic diversity within the cultivated wheats for salt tolerance, exploring the Aegilops cylindrica's genetic diversity for salt tolerance is thus crucial to breed wheat for saline environments. In the current study, wheat genotypes were hybridized with Ae. cylindrica (a hyper salt-tolerant genotype), and amphidiploid plants were produced using embryo rescue and chromosome doubling techniques. Crossability and cytological examinations of amphidiploids and BC1 were performed before sequencing the ITS4/5 and trnE/trnF DNAs to explore the phylogenetic relationships of the amphidiploids and their parents. Finally, amphidiploids were assessed for salt tolerance. Only two common wheat cultivars (‘Chinese Spring’ and ‘Roshan’) were crossable with Ae. cylindrica. The resultant intergeneric hybrids possessed 70 chromosomes, and morphologically either were similar to the male parent in ‘Chinese Spring’ × Ae. cylindrica or tended to be intermediate between parents in ‘Roshan’ × Ae. cylindrica. The phylogenetic tree divided the genotypes into two groups, in which Clade I contained Ae. cylindrica and three amphidiploids, and Clade II consisted of female parents and one amphidiploid. Amphidiploids exhibited significantly higher tolerance to salt stress compared to the female parents (wheat cultivars) in terms of a higher dry matter, lower accumulation of Na, higher K, and higher K/Na ratio in their root and leaf tissues. Taken together, the amphiploid plants might contain valuable salt tolerance factors.
相似文献Cotton fibre quality is a multigenic trait. Genetic modification of different genes to achieve high quality fibre is difficult without knowing the mechanism lying behind genes interaction. Based on background knowledge an attempt to explore the potential structural interactions between Gossypium hirsutum Wlim5 domain1 and Gossypium hirsutum ACTIN-1 proteins was done in current study. Sequence features of the LIM domain1 of GhWlim5 protein were identified through multiple sequence alignment analysis, and a phylogenetic tree was built to identify evolutionary relationships between sequences. Conservation indicated the evolutionary importance of side chain residues and the presence of several aliphatic and/or bulky residues, which stabilize the protein core and facilitate packing of zinc fingers. The structures of GhWlim5 domain1 and GhACTIN-1 proteins were modelled and validated through computational methods. Validation of GhACTIN-1 and GhWlim5 domain1 structures indicated good structural quality with 99.7% and 100% of the favoured number of residues in allowed regions and Z-score, within the ranges of − 9.87 and − 4.17, respectively. Docking analysis indicated various possible modes of interaction between these two proteins with favourable binding affinities. Based on our strong binding interaction results between GhWlim5 domain1 and GhACTIN-1 proteins, we further investigated the role of over-expression of GhWlim5 by transformation in cotton plants under fibre specific promoter and transgenic plants displayed significant increases in fibre strength.
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