Glycine-rich RNA binding protein of Oryza sativa inhibits growth of M15 E. coli cells

<p>Abstract</p> <p>Background</p> <p>Plant glycine-rich RNA binding proteins have been implicated to have roles in diverse abiotic stresses.</p> <p>Findings</p> <p><it>E. coli </it>M15 cells transformed with full-length rice glycine-rich RNA binding protein4 (OsGR-RBP4), truncated rice glycine-rich RNA binding protein4 (OsGR-RBP4ΔC) and rice FK506 binding protein (OsFKBP20) were analyzed for growth profiles using both broth and solid media. Expression of OsGR-RBP4 and OsGR-RBP4ΔC proteins caused specific, inhibitory effect on growth of recombinant M15 <it>E. coli </it>cells. The bacterial inhibition was shown to be time and incubation temperature dependent. Removal of the inducer, IPTG, resulted in re-growth of the cells, indicating that effect of the foreign proteins was of reversible nature. Although noted at different levels of dilution factors, addition of purified Os-GR-RBP4 and OsGR-RBP4ΔC showed a similar inhibitory effect as seen with expression inside the bacterial cells.</p> <p>Conclusions</p> <p>Expression of eukaryotic, stress-associated OsGR-RBP4 protein in prokaryotic <it>E. coli </it>M15 cells proves injurious to the growth of the bacterial cells. <it>E. coli </it>genome does not appear to encode for any protein that has significant homology to OsGR-RBP4 protein. Therefore, the mechanism of inhibition appears to be due to some illegitimate interactions of the OsGR-RBP4 with possibly the RNA species of the trans-host bacterial cells. The detailed mechanism underlying this inhibition remains to be worked out.</p

Observation of CP violation in the B0 meson system

We present an updated measurement of time-dependent CP-violating asymmetries in neutral B decays with the BABAR detector at the PEP-II asymmetric B Factory at SLAC. This result uses an additional sample of Upsilon(4S) decays collected in 2001, bringing the data available to 32 million B-anti-B pairs. We select events in which one neutral B meson is fully reconstructed in a final state containing charmonium and the flavor of the other neutral B meson is determined from its decay products. The amplitude of the CP-violating asymmetry, which in the Standard Model is proportional to sin2beta, is derived from the decay time distributions in such events. The result sin2beta = 0.59 +/- 0.14 (stat) +/- 0.05 (syst) establishes CP violation in the B^0 meson system. We also determine |lambda| = 0.93 +/- 0.09 {stat} +/- 0.03 {syst}, consistent with no direct CP violation.Comment: 8 pages, 2 figures, submitted to Physical Review Letter