Trichophyton rubrum and T. violaceum are prevalent agents of human dermatophyte infections, the former being found on glabrous skin and nail, while the latter is confined to the scalp. The two species are phenotypically different but are highly similar phylogenetically. The taxonomy of dermatophytes is currently being reconsidered on the basis of molecular phylogeny. Molecular species definitions do not always coincide with existing concepts which are guided by ecological and clinical principles. In this article, we aim to bring phylogenetic and ecological data together in an attempt to develop new species concepts for anthropophilic dermatophytes. Focus is on the T. rubrum complex with analysis of rDNA ITS supplemented with LSU, TUB2, TEF3 and ribosomal protein L10 gene sequences. In order to explore genomic differences between T. rubrum and T. violaceum, one representative for both species was whole genome sequenced. Draft sequences were compared with currently available dermatophyte genomes. Potential virulence factors of adhesins and secreted proteases were predicted and compared phylogenetically. General phylogeny showed clear gaps between geophilic species of Arthroderma, but multilocus distances between species were often very small in the derived anthropophilic and zoophilic genus Trichophyton. Significant genome conservation between T. rubrum and T. violaceum was observed, with a high similarity at the nucleic acid level of 99.38 % identity. Trichophyton violaceum contains more paralogs than T. rubrum. About 30 adhesion genes were predicted among dermatophytes. Seventeen adhesins were common between T. rubrum and T. violaceum, while four were specific for the former and eight for the latter. Phylogenetic analysis of secreted proteases reveals considerable expansion and conservation among the analyzed species. Multilocus phylogeny and genome comparison of T. rubrum and T. violaceum underlined their close affinity. The possibility that they represent a single species exhibiting different phenotypes due to different localizations on the human body is discussed.

e Seventy-two A. fumigatus clinical isolates from China were investigated for azole resistance based on mutations of cyp51A. We identified four azole-resistant strains, among which we found three strains highly resistant to itraconazole, two of which exhibit the TR34/L98H/S297T/F495I mutation, while one carries only the TR34/L98H mutation. To our knowledge, the latter has not been found previously in China. The fourth multiazole-resistant isolate (with only moderate itraconazole resistance) carries a new G432A mutation.

Candida albicans is the most common human fungal pathogen for both immunocompetent and immunocompromised individuals. Lysine succinylation is a frequently occurring post-translational modification that is found in many organisms; however, the role of succinylation is still under investigation. Here, we initiated a first screening of lysine succinylation in C. albicans. We identified 1550 succinylation sites from 389 proteins in C. albicans, demonstrating that succinylation is conservative in this organism. However, the lysine succinylation sites showed some difference in C. albicans, with the overlapping rates between C. albicans and other species ranging from 55% for Saccharomyces cerevisiae, 40% for human, 35% for mouse, and to only 16% for Escherichia coli. The further bioinformatics analysis indicated that the succinylated proteins were involved in a wide range of cellular functions with diverse subcellular localizations. Furthermore, we discovered that lysine succinylation could coexist with phosphorylation and/or acetylation in C. albicans. The KEGG enrichment pathway analysis of these succinylated proteins suggested that succinylation may play an indispensable role in the regulation of the tricarboxylic acid cycle. The bioinformatic data obtained from this study therefore enable the depth-resolved physiological roles of lysine succinylation in C. albicans.

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