Résumé
Proteomics, which has been widely used in life science, is an emerging discipline following genomics. It can help to explore the pathogenic mechanism and early onset marker of Bacillus anthracis, playing an important part in the prevention, diagnosis and treatment of B.anthracis. In this paper,the application of proteomics in the research of B.anthracis is reviewed.
Résumé
Shigella flexneri is an infectious pathogen that causes dysentery to human, which remains a serious threat to public health, particularly in developing countries. In this study, the global protein expression patterns of S. flexneri during transition from exponential growth to stationary phase in vitro were analyzed by using 2-D PAGE combined with MALDI-TOF MS. In a time-course experiment with five time points, the relative abundance of 49 protein spots varied significantly. Interestingly, a putative outer membrane protein YciD (OmpW) was almost not detected in the exponential growth phase but became one of the most abundant proteins in the whole stationary-phase proteome. Some proteins regulated by the global regulator FNR were also significantly induced (such as AnsB, AspA, FrdAB, and KatG) or repressed (such as AceEF, OmpX, SodA, and SucAB) during the growth phase transition. These proteins may be the key effectors of the bacterial cell cycle or play important roles in the cellular maintenance and stress responses. Our expression profile data provide valuable information for the study of bacterial physiology and form the basis for future proteomic analyses of this pathogen.
Sujets)
Protéines bactériennes , Biologie informatique , Électrophorèse bidimensionnelle sur gel , Analyse de profil d'expression de gènes , Méthodes , Cinétique , Cartographie peptidique , Protéome , Protéomique , Méthodes , Shigella flexneri , Métabolisme , Virulence , Spectrométrie de masse MALDI , Température , Trypsine , Pharmacologie , VirulenceRésumé
Hydantoinase can be widely used in enzymic production of various amino acids. In order to obtain the hydantoinase genes in Arthrobacter BT801, its chromatosomal DNA is isolated and partialy digested with Sau3A I to collect fragments of about 30kb. Then, this fragment is inserted into the Hpa I and Pst I site of cosmid pKC505. The genomic library was thus constructed by packing in vitro with lambda phage package protein and transfecting E. coli DH5alpha. A positive transformant was selected from the library using thin layer chromatography and other methods. A DNA fragment containing complete hydantoinase genes was sequenced by sub-cloning into pUC18. The gene can express active protein under control of its own promoter and T5 promoter in E. coli. The isolation of the gene established foundition for research and application of the hydantoinase.
Sujets)
Amidohydrolases , Génétique , Métabolisme , Arthrobacter , Génétique , Bactériophage lambda , Génétique , Chromatographie sur couche mince , Clonage moléculaire , Électrophorèse sur gel d'agar , Électrophorèse sur gel de polyacrylamide , Escherichia coli , Génétique , Métabolisme , Banque de gènes , Régions promotrices (génétique) , GénétiqueRésumé
In order to establish a method by which the recombinant suicide plasmids integrated on the chromosome could be recircled, A simple method of transconjugative cloning was established with the helper plasmids pMT999 or pRK2013 and fusion strains of Shigella flexneri which were obtained by screening with in vivo expression technology. And the cloning efficiency with this method is very high.