Escherichia coli strain 397c carries a temperature-sensitive mutation, rpoC397, that removes the last 50 amino acids of the RNA polymerase beta' subunit and is nonpermissive for plating of bacteriophage P2. P2 gor mutants productively infect 397c and define a new gene, lysC, encoded by a reading frame that extensively overlaps the P2 lysis accessory gene, lysB. The unusual location of lysC with...

The genome of most Beet necrotic yellow vein virus (BNYVV) isolates is comprised of four RNAs. The ability of certain isolates to overcome Rz1-mediated resistance in sugar beet grown in the United States and Europe is associated with point mutations in the pathogenicity factor P25. When the virus is inoculated mechanically into sugar beet roots at high density, the ability depends on an alanine...

The structural motif formed between a hammerhead ribozyme and its substrate consists of three RNA double helices in which the sequence 5' to the XUY is termed helix I and the sequence 3' to the XUY helix III. Two hammerhead ribozymes targeted to the tat gene of HIV-1SF2 were designed to study target specificity and the potential effect of helix I mismatch on ribozyme efficacy both in vitro and ...

The problem of representing a positive semidefinite function (=psd) as a sum of squares (=sos) is a very old matter in real algebra and real geometry. Still, it is a difficult question always appealing the specialists. Concerning real analytic germs we can summarize what is known in a few statements. Let X be a irreducible real analytic set germ of dimension d. Any psd f of X is an sos of merom...

We consider the shape of the magnetic Compton profile (MCP), Jmag(pz), in La1.2Sr1.8Mn2O7 for momentum transfer pz along the [110] direction and the associated reciprocal form factor B(r) defined by taking the one-dimensional Fourier transform of Jmag(pz). B(r) is shown to contain a prominent dip at rz1 Å, where the minimum value Bmin of B(r) can be related to the occupancies of the eg orbitals...