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A K Banerjee

Publications and source records attributed to A K Banerjee.

At least 487 records · Page 27Linked to original sources

A unique RNA species involved in initiation of vesicular stomatitis virus RNA transcription in vitro.

Purified virions of vesicular stomatitis virus (VSV) are capable of synthesizing two distinct types of virus-specific RNA in vitro. The first consists of several viral mRNAs which have been previously shown to contain the blocked 5' terminal sequence GpppApApCpApGp and 3' terminal poly(A). The second type of RNA has an unblocked 5' terminus and does not contain poly(A) stretches long enough to bind to oligo (dT)-cellulose columns. It migrates in 20% polyacrylamide gels as a single homogeneous peak with an estimated chain length of 68 nucleotides. Base analysis demonstrated that this small RNA molecule is composed of 48% AMP, 20% CMP, 11% GMP, and 21% UMP. The 5' terminal sequence of the small RNA is ppApCpGp, which appears to be complementary to the 3' terminal sequence of the VSV genome RNA (...PypGpU). These results indicate that this small RNA molecule probably represents the intitiated lead-in RNA segment which is removed during formation of VSV mRNAs by a possible processing mechanism.

Adenosine↗

Analysis of the RNA species isolated from defective particles of vesicular stomatitis virus.

Serial high multiplicity passage of a cloned stock of vesicular stomatitis virus was found to generate defective interfering particles containing three size classes of RNA, with sedimentaiton coefficients of 31 S, 23 S and 19 S. The 31 S and 23 S RNA species were found to be complementary to both the 12 to 18 S and 31 S size classes of VSV mRNAs. The 19 S class of RNA was found to be partially base-paired. All three RNA species were found to contain ppAp at their 5' termini.

Adenine Nucleotides↗

Dependence of translation on 5'-terminal methylation of mRNA.

Many eukaryotic cell and viral mRNAs contain 5'-terminal m7G(5')ppp(5')N. Methylation is important for the in vitro translation of vesicular stomatitis virus and reovirus mRNAs. Unmethylated viral mRNAs are methylated by cell-free extrascts of wheat germ and L cells to form 5'-terminal structures of the type, m7GpppN and m7GpppNm, respectively. Rabbit globin mRNA also contains 5'-terminal 7-methylguanosine (m7G). Removal of the m7G by beta-elimination decreases translation. The efficient binding of mRNA to ribosomes is dependent on the presence of 5'-terminal m7G.

Animals↗

Fructose 1,6-bisphosphate aldolase activity of Rhizobium species.

FDP aldolase was found to be present in the cell-free extracts of Rhizobium leguminosarum, Rhizobium phaseoli, Rhizobium trifolii, Rhizobium meliloti, Rhizobium lupini, Rhizobium japonicum and Rhizobium species from Arachis hypogaea and Sesbania cannabina. The enzyme in 3 representative species has optimal activity at pH 8.4 in 0.2M veronal buffer. The enzyme activity was completely lost by treatment at 60 degrees C for 15 min. The Km values were in the range from 2.38 to 4.55 X 10(-6)M FDP. Metal chelating agents inhibited enzyme activity, but monovalent or bivalent metal ions failed to stimulate the activity. Bivalent metal ions in general were rather inhibitory.

Cell-Free System↗