ABSTRACT
Mammalian expression systems, due to their capacity in post-translational modification, are preferred systems for biopharmaceutical protein production. Several recombinant protein systems have been introduced to the market, most of which are under clinical development. In spite of significant improvements such as cell line engineering, introducing novel expression methods, gene silencing and process development, expression level is unpredictable and unstable because of the random location of integration in the genome. Site-specific recombination techniques are capable of producing stable and high producer clonal cells; therefore, they are gaining more importance in the biopharmaceutical production. Site-specific recombination methods increase the recombinant protein production by specifically inserting a vector at a locus with specific expression trait. The present review focused on the latest developments in site-specific recombination techniques, their specific features and comparisons
ABSTRACT
Aim: The aim of this study was to investigate the VRE frequency and the rate of each gene in isolated enterococci frompatients with intestinal infection in the central region of Iran
Background: Enterococci infections are a public health growing concern due to the glycopeptide antibiotics resistanceespecially vancomycin. Genes, vanA, B, and H contribute to the influence of vancomycin-resistant enterococci [VRE]
Patients and methods: This study was conducted from January to July 2014 in Shahrood university hospital.Enterococci isolation and its antibacterial susceptibility were performed by culturing in Aesculin Azide agar and Kirby-Bauer method, respectively. Vancomycin-resistant genes were screened through conventional PCR, and subsequentlysequenced
Results: Among 265 specimens, 100 isolates revealed enterococci, in which E. faecalis [91%] and E. faecium [9%]. Theisolated enterococci were resistant to vancomycin [6%] and chloramphenicol [21%], whereas their large proportions [94% to100%] were multi-drug resistant. All VRE isolates belonged to E. faecalis, conversely, the E. faecium were susceptible to thesame antibiotic. Both vanA and vanH genes were identified in all VRE isolates, although, no vanB gene was indicated.Homology analysis of sequenced amplicons verified the full length compatibility to the worldwide reported genes
Conclusion: The present study revealed VR E. faecalis in gastroenteritis patients and resistance factor for vanA andvanH genes are coordinated. Since enterococci isolates were all multidrug resistance, increase in VR E. faecalis vanA /vanH in this area could be expected
ABSTRACT
Anterior pituitary glycoprotein hormones include thyroid stimulating hormone, lutinizing hormone, follicule stimulating hormone, and gonadotropine hormone. Each of them contains alpha and beta subunits. The alpha subunit gene is the same in all of these hormones and contains 4 exones and 3 intrones. The beta subunit is responsible for specific function of each hormone. The aim of this study was to clone alpha chain cDNA of glycoprotein hormones in a proper vector for eukaryotic system. To clone cDNA, alpha subunit of glycoprotein hormones was amplified by using one pair primers and T.vector as template and cloned in Not I and Bam HI sites of pcDNA3.1 plasmid. The recombinant plasmid transformed to E.coli Top10F? cell and colonies that contain plasmid were selected by Colony PCR. The accuracy of extracted plasmid of these clones was approved by enzyme digestion and sequencing. Enzyme analysis showed that pcDNA3.1-F351alpha had correct structure and sequencing confirmed by 100% homology of the gene with reported alpha gene in Gene Bank. Because of its proper structure, this plasmid is able to transform to Eukaryotic system and translation