Proteome dataset of mouse macrophage cell line infected with tick-borne encephalitis virus.

We report the proteomic datasets on the mouse macrophage cell line PMJ2R infected with tick-borne encephalitis virus (TBEV) for two and six days. Data were acquired using shotgun ultra-high resolution mass spectrometry. Peptide identifications were done using the Mascot version 2.4 (Matrix Science), and quantification was performed by a label-free approach. Protein profiles of early (two days) and late (six days) stages of infection were compared between each other and the respective control samples. Protein profiles of infected and control samples differed in the number of identified proteins and their relative abundances. Proteins detected in the TBEV-infected cells were involved in various processes related to the infection, including defense response against the virus, regulation of viral process, negative regulation of viral genome replication, RNA binding, or innate immune response. Also, proteins specific for the early and late stages of infection were identified.

Properties of aminopeptidase activity involved in the conversion of vasopressin by rat brain membranes.

Previously it has been shown that vasopressin (VP) and oxytocin are converted by aminopeptidase activity in brain membranes into fragments with potent CNS activities. This report concerns the properties of this enzyme activity, addressed as VP-converting aminopeptidase (VP-AP) activity, in membranes of the rat brain. The VP-AP activity had a pH optimum at pH 7.0 and had a Km of 17 microM for its action on VP. Amastatin was the most potent aminopeptidase inhibitor. Enzyme activity was inhibited by relatively low concentrations of metal chelators. Treatment of brain membranes by EDTA resulted in loss of enzyme activity that was completely reversed by 10 microM Zn2+, indicating that VP-AP activity is a metallopeptidase. Several VP analogues and fragments, in particular VP(1-8), inhibited the action of enzyme activity on VP. Among peptides unrelated to VP, angiotension I, somatostatin, and porcine ACTH(1-39) markedly inhibited enzyme activity. Solubilization of VP-AP activity from brain membranes and gel filtration on Sephadex G200 showed two peaks of activity, one eluting with an apparent mass of about 140 kDa, the other in the void volume. Gel filtration fractions were able to convert [3H][Phe3]VP in a step-wise fashion. The VP-AP-like activity was found in many tissues outside the brain. Highest activity was present in lung, kidney, parts of the gastrointestinal tract, ovary, and uterus. The results indicate that VP-AP activity is a widely distributed enzyme with probably multiple functions, one of which involves the metabolism of vasopressin in the brain.

Inhibition of human serum oxytocinase (cystine aminopeptidase, E. C. 3.4.11.3) by GnRH peptides.

The hydrolysis of H-Cys(Bzl)-NH-Meq by human serum oxytocinase (E.C. 3.4.11.3) was inhibited non-competitively by various pyroglutamyl peptides. The most effective were the chicken GnRH II (Ki = 6 x 10(-6) mol l-1) and salmon GnRH (Ki = 12 x 10(-6) mol l-1), while the inhibitory potency of human GnRH was substantially lower (Ki = 60.0 x 10(-6) mol l-1). Variations in inhibitory potency of individual peptides reflected mostly the differences in N-terminal and C-terminal parts of the molecules.

Macromolecular synthesis accompanying the transition from spores to vegetative forms of Streptomyces granaticolor.

The rates of RNA, protein and DNA synthesis were estimated in synchronously germinating spores of Streptomyces granaticolor. Rapid uptake of labelled precursors of RNA and proteins was observed after 20 s. The germination process took place through a sequence of time-ordered events. RNA synthesis started after 3 min of germination, protein synthesis began at 4 min and net DNA synthesis at 60-70 min of germination. A characteristic feature of germination was the biphasic pattern in the rate of RNA and protein synthesis. Spores of Streptomyces granaticolor were sensitive to actinomycin D, rifampicin and chloramphenicol even at the start of germination. Protein synthesis during germination was dependent on new mRNA synthesis and was independent during the first 60-70 min on replication of the spore genome.