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Jiang, Y.-L.

Publications and source records attributed to Jiang, Y.-L..

3 recordsLinked to original sources

Proposal of two new genera and seventy-seven new species of ascomycetous yeasts isolated from China

Ascomycetous yeasts belong to Saccharomycotina and Taphrinomycotina, with about 1,200 described species distributed worldwide. More than 300 ascomycetous yeast species have been reported from China, which indicates that China possesses a hotspot with high yeast diversity. However, our knowledge of yeast diversity and distribution remains limited, and this area needs to be explored in depth. Here we describe 77 new ascomycetous yeast species with 195 isolates obtained over the past two decades during the continuous yeast diversity surveys in China, based on the phylogenetic analyses of the sequences of D1/D2 domains of the large subunit (LSU) and the internal transcribed spacer region including the 5.8S rDNA (ITS) of the nuclear ribosomal DNA (rDNA). The average nucleotide identity (ANI) analysis was used to delimitate closely related species with low sequence heterogeneity in the ITS and D1/D2 regions. Seventy-five of these new species belong to 35 genera in the Saccharaomycotina, while the other two are distributed in Taphrina of the Taphrinomycotina. In addition, we propose two new genera, namely Gaboromyces gen. nov. and Yurkovozyma gen. nov.

microbiology↗

Nonribosomal peptide synthetases require dynamic interaction between modular domains

Nonribosomal peptide synthetases (NRPSs) are large multidomain enzymes for the synthesis of a variety of bioactive peptides in a modular and pipelined fashion. Here, we investigated how the condensation (C) domain and the adenylation (A) domain cooperate with each other for the efficient catalytic activity in microcystin NRPS modules. We solved two crystal structures of the microcystin NRPS modules, representing two newly identified conformations in the NRPS catalytic cycle. Our data reveals that the dynamic interaction between the C and the A domains in these modules are mediated by the conserved "RXGR" motif, and this interaction is important for the adenylation activity. Furthermore, the "RXGR" motif-mediated dynamic interaction and its functional regulation is prevalent in different NRPSs modules possessing both the A and the C domains. This study provides new insight into the catalytic mechanism of NRPSs and should inspire novel ideas in NRPS enzyme engineering in synthetic biology.

biochemistry↗

Analysis of Structure and function by the LysR-Type Transcriptional Regulator CbbR of Nostoc sp. PCC 7120

The LysR-type Calvin-Benson-Bassham cycle transcriptional regulator CbbR plays an important role in CO2 fixation in carbon metabolism in nature, which regulates the gene expression of the key enzyme RibisCO in the Calvin-Benson-Bassham (CBB) cycle. In this study, we optimized the conditions for the transformation, expression, and purification of CbbR in the model algae Nostoc sp. PCC 7120, obtained nick-DNA fragments that could tightly bind to CbbR_7120, and finally obtained CbbR protein crystals. These findings provide great assistance for the final crystallization of CbbR to solve the crystal structure of CbbR, and lay the foundation for understanding the mechanism of CO2 fixation in the CBB cycle.

biochemistry↗