Endophthalmitis is a serious ophthalmic disease characterized by changes in the eye's posterior segment,such as hypopyon and intraocular inflammation,vitritis being a hallmark.Infection-caused endophthalmitis can ...Endophthalmitis is a serious ophthalmic disease characterized by changes in the eye's posterior segment,such as hypopyon and intraocular inflammation,vitritis being a hallmark.Infection-caused endophthalmitis can lead to irreversible vision loss,accompanied by eye pain or eye distention,and in the most severe cases the removal of the eyeball.Microorganisms such as bacteria,fungi,viruses,and parasites typically account for the disease and the entry pathways of the microbial can be divided into either endogenous or exogenous approaches,according to the origin of the etiological agents.Exogenous endophthalmitis can be derived from various occasions(such as postoperative complications or trauma)while endogenous endophthalmitis results from the bloodstream which carries pathogens to the eye.This review aims to summarize the application of new technology in pathogen identification of endophthalmitis so as to prevent the disease and better guide clinical diagnosis and treatment.展开更多
Genome sequencing projects revealed massive cryptic gene clusters encoding the undiscovered secondary metabolites in Streptomyces. To investigate the metabolic products of silent gene clusters in Streptomyces chattano...Genome sequencing projects revealed massive cryptic gene clusters encoding the undiscovered secondary metabolites in Streptomyces. To investigate the metabolic products of silent gene clusters in Streptomyces chattanoogensis L10(CGMCC 2644), we used site-directed mutagenesis to generate ten mutants with point mutations in the highly conserved region of rpsL(encoding the ribosomal protein S12) or rpoB(encoding the RNA polymerase β-subunit). Among them, L10/RpoB(H437 Y) accumulated a dark pigment on a yeast extract-malt extract-glucose(YMG) plate. This was absent in the wild type. After further investigation, a novel angucycline antibiotic named anthrachamycin was isolated and determined using nuclear magnetic resonance(NMR) spectroscopic techniques. Quantitative real-time polymerase chain reaction(qRT-PCR) analysis and electrophoretic mobility shift assay(EMSA) were performed to investigate the mechanism underlying the activation effect on the anthrachamycin biosynthetic gene cluster. This work indicated that the rpoB-specific missense H437 Y mutation had activated anthrachamycin biosynthesis in S. chattanoogensis L10. This may be helpful in the investigation of the pleiotropic regulation system in Streptomyces.展开更多
文摘Endophthalmitis is a serious ophthalmic disease characterized by changes in the eye's posterior segment,such as hypopyon and intraocular inflammation,vitritis being a hallmark.Infection-caused endophthalmitis can lead to irreversible vision loss,accompanied by eye pain or eye distention,and in the most severe cases the removal of the eyeball.Microorganisms such as bacteria,fungi,viruses,and parasites typically account for the disease and the entry pathways of the microbial can be divided into either endogenous or exogenous approaches,according to the origin of the etiological agents.Exogenous endophthalmitis can be derived from various occasions(such as postoperative complications or trauma)while endogenous endophthalmitis results from the bloodstream which carries pathogens to the eye.This review aims to summarize the application of new technology in pathogen identification of endophthalmitis so as to prevent the disease and better guide clinical diagnosis and treatment.
基金Project supported by the National Natural Science Foundation of China(Nos.31520103901 and 3173002)
文摘Genome sequencing projects revealed massive cryptic gene clusters encoding the undiscovered secondary metabolites in Streptomyces. To investigate the metabolic products of silent gene clusters in Streptomyces chattanoogensis L10(CGMCC 2644), we used site-directed mutagenesis to generate ten mutants with point mutations in the highly conserved region of rpsL(encoding the ribosomal protein S12) or rpoB(encoding the RNA polymerase β-subunit). Among them, L10/RpoB(H437 Y) accumulated a dark pigment on a yeast extract-malt extract-glucose(YMG) plate. This was absent in the wild type. After further investigation, a novel angucycline antibiotic named anthrachamycin was isolated and determined using nuclear magnetic resonance(NMR) spectroscopic techniques. Quantitative real-time polymerase chain reaction(qRT-PCR) analysis and electrophoretic mobility shift assay(EMSA) were performed to investigate the mechanism underlying the activation effect on the anthrachamycin biosynthetic gene cluster. This work indicated that the rpoB-specific missense H437 Y mutation had activated anthrachamycin biosynthesis in S. chattanoogensis L10. This may be helpful in the investigation of the pleiotropic regulation system in Streptomyces.
