Viruses including baculoviruses are obligatory parasites, as their genomes do not encode all the proteins required for replication. Therefore, viruses have evolved to exploit the behavior and the physiology of their h...Viruses including baculoviruses are obligatory parasites, as their genomes do not encode all the proteins required for replication. Therefore, viruses have evolved to exploit the behavior and the physiology of their hosts and olden coevolved with their hosts over millions of years. Recent comparative analyses of complete genome sequences of baculoviruses revealed the patterns of gene acquisitions and losses that have occurred during baculovirus evolution. In addition, knowledge of virus genes has also provided understanding of the mechanism of baculovirus infection including replication, species-specific virulence and host range. The Bm8 gene of Bombyx mori nucleopolyhedrovirus （NPV） and its homologues are found only in group I NPV genomes. The Autographa californica NPV Ac 16 gene is a homologue of Bm8 and, encodes a viral structural protein. It has been shown that BmS/Ac 16 interacts with baculoviral and cellular proteins. BmS/Ac 16 interacts with baculoviral IE1 that is facilitated by coiled coil domains, and the interaction with IE1 is important for Bin8 function. Acl6 also forms a complex with viral FP25 and cellular actin and associates with membranes via palmitoylation. These data suggested that this gene family encodes a multifunctional protein that accomplishes specific needs of group I NPVs.展开更多
Polymyxin acts as an ultimate line of refuge against the severe infections by multidrug-resistant Gram- negative pathogens. This conventional idea is challenged dramatically by the recent discovery of mobile colistin ...Polymyxin acts as an ultimate line of refuge against the severe infections by multidrug-resistant Gram- negative pathogens. This conventional idea is challenged dramatically by the recent discovery of mobile colistin resistance gene （mcr-1） is prevalent in food animals and human beings worldwide. More importantly, the mcr-1 gene was found to be co-localized with other antibiotic resistance genes, raising the possibility that super-bugs with pan-drug resistance are emerging. However, little is reported on the genomes of the mcr-l-positive bacterial host reservoirs. Here we report genome sequencing of three human isolates of the mcr-l-positive Escherichia coli （E15004, E15015 and E15017） and define general features through analyses of bacterial comparative genomics. Fur- ther genomic mining together with sequence typing allowed us to elucidate that the MCR-l-carrying E. coli E15017 belongs to the sequence type ST648 and copro- duces extended-spectrum β-1actamase （ESBL）. Given the fact that ST648 has been known to associate New Delhi metallo-β-1actamase 1 or ESBL, with either our results highlighted the possibility of ST648 as an epidemic clone with multidrug resistances.展开更多
文摘Viruses including baculoviruses are obligatory parasites, as their genomes do not encode all the proteins required for replication. Therefore, viruses have evolved to exploit the behavior and the physiology of their hosts and olden coevolved with their hosts over millions of years. Recent comparative analyses of complete genome sequences of baculoviruses revealed the patterns of gene acquisitions and losses that have occurred during baculovirus evolution. In addition, knowledge of virus genes has also provided understanding of the mechanism of baculovirus infection including replication, species-specific virulence and host range. The Bm8 gene of Bombyx mori nucleopolyhedrovirus （NPV） and its homologues are found only in group I NPV genomes. The Autographa californica NPV Ac 16 gene is a homologue of Bm8 and, encodes a viral structural protein. It has been shown that BmS/Ac 16 interacts with baculoviral and cellular proteins. BmS/Ac 16 interacts with baculoviral IE1 that is facilitated by coiled coil domains, and the interaction with IE1 is important for Bin8 function. Acl6 also forms a complex with viral FP25 and cellular actin and associates with membranes via palmitoylation. These data suggested that this gene family encodes a multifunctional protein that accomplishes specific needs of group I NPVs.
基金This work was supported by Zhejiang Provincial Natural Science Foundation for Distinguished Young Scholars （LR15H190001）, the National Natural Science Foundation of China （31570027）, and a start-up package from Zhejiang University （Y.F.）. Dr. Feng is a recipient of the ＂Young 1000 Talents＂ Award.
文摘Polymyxin acts as an ultimate line of refuge against the severe infections by multidrug-resistant Gram- negative pathogens. This conventional idea is challenged dramatically by the recent discovery of mobile colistin resistance gene （mcr-1） is prevalent in food animals and human beings worldwide. More importantly, the mcr-1 gene was found to be co-localized with other antibiotic resistance genes, raising the possibility that super-bugs with pan-drug resistance are emerging. However, little is reported on the genomes of the mcr-l-positive bacterial host reservoirs. Here we report genome sequencing of three human isolates of the mcr-l-positive Escherichia coli （E15004, E15015 and E15017） and define general features through analyses of bacterial comparative genomics. Fur- ther genomic mining together with sequence typing allowed us to elucidate that the MCR-l-carrying E. coli E15017 belongs to the sequence type ST648 and copro- duces extended-spectrum β-1actamase （ESBL）. Given the fact that ST648 has been known to associate New Delhi metallo-β-1actamase 1 or ESBL, with either our results highlighted the possibility of ST648 as an epidemic clone with multidrug resistances.
