We identify here a pattern in the transcription start sites (+1A or +1G) of sigma(A)-dependent promoters genes that are up-/downregulated response to amino acid starvation (stringent response) Bacillus subtilis. Upregulated initiate mostly with ATP and downregulated GTP. These appear be sensitive changes initiating nucleoside triphosphate concentrations. During stringent B. subtilis, when GTP levels change reciprocally, identity +1 position (A G) these is factor important their regulation....

Abstract Cell differentiation depends mainly on specific mRNA expression. To quantify the expression of a particular gene, normalisation with respect to reference gene is carried out. This based assumption that constant during development, in different cells or tissues after treatment. Xenopus laevis studies have frequently used eEF‐1 alpha, GAPDH, ODC, L8, and H4 as genes. The aim this work was examine, by real‐time RT‐PCR, profiles above‐mentioned five genes early development X. . It shown...

The affinity of chemically synthetized analogues the 3′ terminus phenylalanyl‐tRNA and leucyl‐tRNA for aminoacyl‐tRNA binding site Escherichia coli elongation factor‐Tu · GTP complex (EF‐Tu GTP) increases in order A(Phe)°C‐A(Leu)<pA(Phe)≤C‐A(Phe)<amino‐acyl‐tRNA [2′(3′)‐ O ‐ l ‐phenylalanyladenosine<cytidylyl‐(3′≤5′)‐2′(3′)‐ ‐leucyladenosine≤2′(3′)‐ 0 ‐phenylalanyladenosine 5′‐phosphate<cytidylyl‐(3′→ 5′)‐2′(3′)‐ ‐phenylalanyladenosine<aminoacyl‐tRNA], as we revealed using...

In bacteria, rapid changes in gene expression can be achieved by affecting the activity of RNA polymerase with small molecule effectors during transcription initiation. An important effector is initiating nucleoside triphosphate (iNTP). At some promoters, an increasing iNTP concentration stimulates promoter activity, while a decreasing has opposite effect. Ribosomal (rRNA) promoters from Gram-positive Bacillus subtilis are regulated their iNTP. Yet, sequences these do not emulate sequence...

Elongation factor EF‐Tu from Escherichia coli was labelled with N ‐[ 14 C]tosyl‐L‐phenylalanylchloromethane, digested trypsin and the peptides obtained separated by HPLC. The only radioactive peak recovered corresponded to tryptic peptide containing residues 75–98. Sequencing of automated Edman degradation identified cysteine 81 as site ‐tosyl‐L‐phenylalanylchloromethane modification. These results confirm importance this residue for interaction aminoacyl‐tRNAs.

Complexes of Escherichia coli elongation factor EF‐Tu with GTP or and aminoacyl‐tRNA were photo‐oxidized by irradiation visible light in the presence rose bengal dye. was isolated, digested trypsin, resulting tryptic peptides separated high‐performance liquid chromatography (HPLC), position most on chromatogram determined. Irradiation complexes resulted inactivation (as tested its capacity to interact aminoacyl‐tRNA) accompanied loss histidine residues revealed amino acid analysis) decrease...

Real-time PCR tomography is a novel, quantitative method for measuring localized RNA expression profiles within single cells. We demonstrate its usefulness by dissecting an oocyte from Xenopus laevis into slices along animal–vegetal axis, extracting and the levels of 18 selected mRNAs real-time RT-PCR. This identified two classes mRNA, one preferentially located towards animal, other vegetal pole. each group show comparable intracellular gradients, suggesting they are produced similar...

RNA polymerase (RNAP) is an essential enzyme that responsible for transcription of DNA into RNA. It a multisubunit enzyme, and its composition well conserved throughout all bacterial species. The core composed dimer made from two α subunits holds together the large subunits, β β′, form active site. ω, small subunit aids RNAP assembly, binds to β′. One several σ required associate with holoenzyme can recognize specific sequences, promoters, where initiates.1-3 Despite high level homology...

Mature Xenopus laevis spermatozoa are capable of binding plasmid pAPrC carrying the complete Rous sarcoma virus (RSV) DNA. Each sperm cell associates, on an average, with 70–160 molecules DNA in a DNase resistant form, if were exposed to at concentration 1.0–1.4 μg/107 cells. Fertilization pAPrC-treated induced developmental malformations 25–30% embryos. Immunohistochemical analysis tissue sections from defective animals revealed aberrations myotomal structures, and increased expression...

A Cys residue located in the second consensus sequence element ( D CP G ) of GTP‐binding region is highly conserved bacterial elongation factors (EF) Tu. Chemical modification this Cys81 EF‐Tu from Escherichia coli by N ‐tosyl‐ l ‐phenylalanine chloromethane [Jonák, J., Petersen, T. E., Clark, B. F. C. & Rychlík, I. (1982) FEBS Lett. 150 , 485–488], and homologous residues other EF‐Tu, selectively blocks binding Xaa‐tRNA. We have substituted with Gly using site‐directed mutagenesis...

The mRNA-directed binding of aminoacyl-tRNA to the ribosome requires a special protein factor EF-T, and GTP.A ternary complex between aminoacyl-tRNA, GTP is formed as an intermediate from which ~~oacyl-t~A transfe~ed ribosomal recognition site (reviewed [ 11). it main feature that in form .GTP able discriminate aminoacylated non-or acylaminoacyfated tRNAs [2][3][4].This provided basis for accumulat~g evidence 3'-terminus involved reaction elongation T, [S-7].Therefore, we prepared two...

Mutation of Pro82 into Thr, a residue situated in the second element (D80CPG83) consensus sequence proposed to interact with GTP/GDP GTP-binding proteins was introduced via site-directed mutagenesis isolated guanine nucleotide-binding domain (G domain) elongation factor Tu. G domainPT82 displays virtually no GTPase activity. As major change, apparent inhibition reaction is associated appearance autophosphorylating activity, as ras product p21 case mutation Ala59----Thr, corresponding 82...

Recombinant mesophilic Escherichia coli (Ec) and thermophilic Bacillus stearothermophilus (Bst) elongation factors EF-Tus, their isolated G-domains, six chimeric EF-Tus composed of domains either EF-Tu were prepared, GDP/GTP binding activities thermostability characterized. BstEF-Tu BstG-domain bound GDP GTP with affinities in nanomolar submicromolar ranges, respectively, fully comparable those EcEF-Tu. In contrast, the EcG-domain nucleotides much lower, micromolar affinities. The exchange 2...

Digestion of ribosomes by ribonuclease T 1 results in the inactivation peptidyl transferase and binding ability donor site. However, activity acceptor site is not affected digestion. The sites ribonuclease‐treated retain their original sensitivity to chloramphenicol, spiramycin, erythromycin lincomycin. 50‐S ribosomal subunits loss same way as digestion 70‐S either intact or recombined from 30‐S subunits. does change after Erythromycin, bound before , decreases rate transferase, whereas...

Proteome analyses revealed that elongation factor-Tu (EF-Tu) is associated with cytoplasmic membranes of Gram-positive bacteria and outer Gram-negative bacteria. It still debatable whether EF-Tu located on the external side or internal membranes. Here, we have generated two new monoclonal antibodies (mAbs) polyclonal rabbit against pneumococcal EF-Tu. These were used to investigate amount surface-exposed viable using a flow cytometric analysis. The control recognizing surface protein A...