Interactions of the homodimeric Escherichia coli beta clamp with

Interactions of the homodimeric Escherichia coli beta clamp with its known partners involves multiple surfaces, including a hydrophobic cleft located near the C-terminus of each clamp protomer.\n\nResults: A mutant E. coli

beta clamp protein lacking a functional hydrophobic cleft (beta(C)) complemented the temperature sensitive growth phenotype of a strain bearing the dnaN159 allele, which encodes a thermolabile mutant clamp protein (beta 159). Complementation was conferred by a beta(C)/beta 159 heterodimer, and was observed only in the absence of the dinB gene, which encodes DNA polymerase IV (Pol IV). Furthermore, the complemented strain was proficient for umuDC (Pol V) -dependent ultraviolet light (UV) -induced mutagenesis.\n\nConclusions: Our results suggest that a single cleft in the homodimeric E. coli beta sliding Selleckchem Cl-amidine clamp protein is sufficient to support both ZD1839 order cell viability, as well as Pol III, Pol IV, and Pol V function in vivo. These

findings provide further support for a model in which different Pols switch places with each other on DNA using a single cleft in the clamp.”
“A [3,3]-rearrangement that is used for facile construction of chiral allenamides is described. A propargylic alcohol, a chlorophosphite, and Cbz-azide are combined to provide a propargylic phosphorimidate that, in the presence of catalytic palladium(II), rearranges to an allenamide. By varying the substitution pattern on the propargylic alcohol, mono-, di-, and trisubstituted allenamides can be accessed in good yields. Additionally, the use of an enantiomerically enriched propargylic alcohol enables the preparation of stereochemically Crenigacestat defined allenamides.”
“Plants respond to pathogen attack by transcriptionally regulating defense-related

genes via various types of transcription factors. We identified a transcription factor in rice, OsNAC111, belonging to the TERN subgroup of the NAC family that was transcriptionally upregulated after rice blast fungus (Magnaporthe oryzae) inoculation. OsNAC111 was localized in the nucleus of rice cells and had transcriptional activation activity in yeast and rice cells. Transgenic rice plants overexpressing OsNAC111 showed increased resistance to the rice blast fungus. In OsNAC111-overexpressing plants, the expression of several defense-related genes, including pathogenesis-related (PR) genes, was constitutively high compared with the control. These genes all showed blast disease-responsive expression in leaves. Among them, two chitinase genes and one beta-1,3-glucanase gene showed reduced expression in transgenic rice plants in which OsNAC111 function was suppressed by a chimeric repressor (OsNAC111-SRDX). OsNAC111 activated transcription from the promoters of the chitinase and beta-1,3-glucanase genes in rice cells. In addition, brown pigmentation at the infection sites, a defense response of rice cells to the blast fungus, was lowered in OsNAC111-SRDX plants at the early infection stage.

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