Characterization of cultivated fungi isolated from grape marc wastes through the use of amplified rDNA restriction analysis and sequencing

Microbial assessment of grape marc wastes, the residual solid by-product of the wine-industry, was performed by identifying phylogenetically the fungal culturable diversity in order to evaluate environmental and disposal safety issues and to discuss ecological considerations of applications on agricultural land. Fungal spores in grape marc were estimated to 4.7×10⁶ per g dry weight. Fifty six fungal isolates were classified into eight operational taxonomic units (OTUs) following amplified ribosomal DNA restriction analysis (ARDRA) and colony morphology. Based on 18S rRNA gene and 5.8S rRNA gene-ITS sequencing, the isolates representing OTUs #1, #2, #3, and #4, which comprised 44.6%, 26.8%, 12.5%, and 5.3%, respectively, of the number of the total isolates, were identified as Aspergillus fumigatus, Bionectria ochroleuca, Haematonectria haematococca, and Trichosporon mycotoxinivorans. The isolates of OTU#5 demonstrated high phylogenetic affinity with Penicillium spp., while members of OTUs #6 and #7 were closer linked with Geotrichum candidum var. citri-aurantii and Mycocladus corymbifer, respectively (95.4 and 97.9% similarities in respect to their 5.8S rRNA gene-ITS sequences). The OTU#8 with a single isolate was related with Aspergillus strains. It appears that most of the fungal isolates are associated with the initial raw material. Despite the fact that some of the species identified may potentially act as pathogens, measures such as the avoidance of maintaining large and unprocessed quantities of grape marc wastes in premises without adequate aeration, together with its suitable biological treatment (e.g., composting) prior to any agriculture-related application, could eliminate any pertinent health risks.     

A cerebellar-thalamocortical pathway drives behavioral context-dependent movement initiation

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Design, synthesis and catalytic activity of a serine protease synthetic model

Summary The design, synthesis and catalytic properties of a cyclic branched peptide carrier that possesses the catalytic triad residues of the serine proteases is reported. The synthesis of the peptide model was totally completed on solid support using three different orthogonal amino protecting groups. Hydrolytic activity measurements against Suc-Ala-Ala-Ala-pNA substrate showed that it is hydrolysed by the peptide model to a small extent. Despite this small hydrolytic activity, it is the first time, to our knowledge, that hydrolysis of such a substrate is reported by an enzyme model compound. Contrary, this enzyme model peptide showed considerable activity against the Boc-Ala-pNP substrate (k _cat =0.414 min⁻¹ andK _m =0.228 mm). These results suggest that the designed carrier brings in appropriate contact the catalytic triad residues (Ser, His, Asp) resulting in the obtained hydrolytic activity.