objective: cell vital function has correlation with mechanical loadings that cell experiences. here, effects of in-vitro combined cyclic-static stretch on proliferation of human mesenchymal stem cell (hmsc) were evaluated. materials and methods: hmscs were cultured on gelatin coated elastic membranes, and exposed to stretch loading. four different regimes of cyclic, static, combined cyclic-sta...

Active eukaryotic RNA polymerase II (RNAP II) was purified by immunoaffinity chromatography, using a monoclonal antibody (mAb) that reacts with the highly conserved heptapeptide repeat of the largest subunit. This mAb (designated SWG16) was conjugated to CNBr-activated Sepharose and used to purify RNAP II from wheat germ and calf thymus. The subunit composition of the immunoaffinity-purified en...

ABSTRACT The Trojan horse Escherichia coli antibiotic microcin C (McC) consists of a heptapeptide attached to adenosine through a phosphoramidate linkage. McC is synthesized by the MccB enzyme, which terminally adenylates the ribosomally synthesized heptapeptide precursor MccA. The peptide part is responsible for McC uptake; it is degraded inside the cell to release a toxic nonhydrolyzable aspa...

Pulmonate snails have a more complex array of cardioexcitatory peptides than other molluscs, and Helix has a more complex array than most other pulmonates. Since a full characterisation of the cardioexcitatory peptides is necessary for an understanding of physiology, we sought to identify the members of two families of such peptides - the small cardioactive peptides (SCPs) and the FMRFamide-rel...

The aim of this study was to investigate the action of the heptapeptide angiotensin-(l-7) on the spontaneous activity of paraventricular neurons using microiontophoresis. Recent immunocytochemical investigations have shown that this product of angiotensin I is predominantly located in cells and fibers of the forebrain and brain stem. Our results show that most neurons in the paraventricular nuc...

The aim of this study was to investigate the action of the heptapeptide angiotensin-(1-7) on the spontaneous activity of paraventricular neurons using microiontophoresis. Recent immunocytochemical investigations have shown that this product of angiotensin I is predominantly located in cells and fibers of the forebrain and brain stem. Our results show that most neurons in the paraventricular nuc...

New therapeutic agents able to block HIV-1 replication are eagerly sought after to increase the possibilities of treatment of resistant viral strains. In this report, we describe a rational strategy to identify small peptide sequences owning the dual property of penetrating within lymphocytes and of binding to a protein target. Such sequences were identified for two important HIV-1 regulatory p...

Gene-inactivation studies point to the involvement of OxyB in catalyzing the first oxidative phenol coupling reaction during glycopeptide antibiotic biosynthesis. The oxyB gene has been cloned and sequenced from the vancomycin producer Amycolatopsis orientalis, and the hemoprotein has been produced in Escherichia coli, crystallized, and its structure determined to 1.7-A resolution. OxyB gave UV...

p53R2 is a newly identified subunit of ribonucleotide reductase (RR) and plays a crucial role in supplying precursors for DNA repair in a p53-dependent manner. In our current work, all three human RR subunit proteins (p53R2, hRRM2, and hRRM1) were prokaryotically expressed and highly purified. Using an in vitro [H]CDP reduction assay, the activity of RR reconstituted with either p53R2 or hRRM2 ...

Despite the potential advantages of 32P over other isotopes for radioimmunotherapy, its development as a therapeutic has been hindered by the difficulty of the labeling chemistry. Recently, a heptapeptide [Kemptide (KPT)] has been chemically conjugated to antibodies, and the conjugates have successfully been labeled with 32P enzymatically by using bovine protein kinase. By using genetic enginee...