Identification and characterization of a translation arrest motif in VemP by systematic mutational analysis.

VemP ( protein xport onitoring olypeptide) is a secretory protein comprising 159 amino acid residues, which functions as a secretion monitor in and regulates expression of the downstream genes. When VemP export is compromised, its translation specifically undergoes elongation arrest at the position where the Gln codon of encounters the P-site in the translating ribosome, resulting in up-regulation of V.SecDF2 production.

Investigation of B-Z transitions with DNA oligonucleotides containing 8-methylguanine.

Among various Z-form DNA inducers, such as transition metal complexes, polyamines and high ionic concentrations, 8-methylguanine have received attention as efficient chemical modifications. Although it is clear that m8-modified guanine base markedly stabilizes the Z conformation of short oligonucleotides under physiological salt conditions, how sequence composition affects the preference of Z-DNA is still not well established. In this study, various oligomers of d(CG)n or d(GC)n containing either 8-methylguanine in a different position were synthesized and their capacity of stabilizing Z-DNA were evaluated by CD spectra and then compared with each other.