Disease relevance of tryptacin

• The E. coli trpR gene encodes the 108 amino acid long trp repressor [1].
• The regulatory region of the trp operon of Serratia marcescens [2].
• These phages, derivatives of Salmonella phage P22 that have substitutions of synthetic, symmetric trp operators for the P22 mnt operator, provide a genetic assay for DNA binding in vivo [3].
• In this article, we extend this knowledge by analyzing the predicted regulatory regions in the trp operons of other fully sequenced Gram-positive bacteria [4].
• Null mutations in trp cause impairment of visual transduction, mislocalization of INAD, and retinal degeneration [5].

High impact information on tryptacin

• Contrary to current models of excitation and TRP channel function, we demonstrate that the transient phenotype of trp mutants can be explained by CAM regulation of the TRPL channel rather than by the loss of a store-operated conductance leading to depletion of the internal stores [6].
• Expression in COS cells of two full-length cDNAs encoding human trp homologs, Htrp1 and Htrp3, increased CCE [7].
• Studies on visual signal transduction in Drosophila led to the hypothesis that a protein encoded in trp may be a component of CCE channels [7].
• DNA recognition by lac repressor and catabolite activator protein is greatly stimulated, while specific aroH DNA recognition by trp repressor is inhibited [8].
• The DNA sequence at tL shows striking homologies with trp t', a terminator also strongly affected in vitro by the nusA protein [9].

Chemical compound and disease context of tryptacin

• Thus B. subtilis and Escherichia coli respond to identical regulatory signals, tryptophan and uncharged tRNA(Trp), yet they employ different mechanisms in regulating trp gene expression [10].
• The trp, phe, his, thr, and leu operons of enteric bacteria are regulated by a transcriptional attenuation mechanism [11].
• Equilibrium and kinetic studies of the urea-induced unfolding of trp aporepressor from Escherichia coli were performed to probe the folding mechanism of this intertwined, dimeric protein [12].
• Both compounds were assayed for mutagenicity in a series of Escherichia coli WP2 strains (trp- leads to trp+) and in several strains of Salmonella typhimurium (his- leads to his+), in the presence and absence of a post-mitochondrial supernatant (S9) from livers of rats treated with Aroclor 1254 [13].
• The refolding kinetics of Escherichia coli trp aporepressor were monitored using stopped-flow far-ultraviolet circular dichroism and 8-anilino-1-naphthalene sulfonate fluorescence spectroscopy [14].

Biological context of tryptacin

• Because the desamino analogues thus cause derepression of operons under control of the trp repressor, they appear to be 'inducers'. We have determined the crystal structure of the pseudorepressor and refined it to 1.65 A [15].
• Determinants of repressor/operator recognition from the structure of the trp operator binding site [16].
• The tandem complex model accounts for the mutational sensitivity of all trp operator base pairs [17].
• Here we present the high-resolution crystal structure of the trp operator region that is most important in the recognition process [16].
• The methylation protection assay shows that Trp repressor binds in two successive major grooves of the trpR operator, three successive major grooves of the aroH operator, and four successive major grooves of the trp operator [18].

Anatomical context of tryptacin

• Abolishing Ca2+ influx in wild-type photoreceptors mimicked inactivation, while raising Ca2+ by blocking Na+/Ca2+ exchange prevented inactivation in trp [19].
• This and the possibility that trp leader RNA is translated suggest a model for regulation of transcription termination that is based on ribosome movement along the RNA and a shift between alternative RNA base-pairing configuration [20].
• Human PDI was expressed to the Escherichia coli periplasm, by using a plasmid encoded ompA-PDI fusion under the control of the trp promoter [21].
• The product expressed from the trp promoter system had high antiviral activity and displayed biological effects similar to those of Namalwa interferon on natural killer cell activity and in a Daudi cell growth inhibition assay [22].
• Isolation, cloning, and characterisation of a trp homologue from squid (Loligo forbesi) photoreceptor membranes [23].

Associations of tryptacin with other chemical compounds

• As well as being a major charge carrier for the light-induced current, Ca2+ influx via the trp-dependent channels appears to be required for refilling Ca2+ stores sensitive to inositol 1,4,5-trisphosphate and for feedback regulation (light adaptation) of the transduction cascade [24].
• An atomic view of the L-tryptophan binding site of trp repressor [25].
• Alternative secondary structures of leader RNAs and the regulation of the trp, phe, his, thr, and leu operons [11].
• The lesion was shown by DNA sequencing to be a G to C transversion at nucleotide 5528 of the trp operon, resulting in a Gly to Arg switch at codon 281 [26].
• Analysis of the trp cage peptides by circular dichroism and NMR indicated that the structure and stability of the trp cage miniprotein was controllable based on the conformational bias of the proline derivative [27].

Gene context of tryptacin

• To explain the residual photoresponse that remains in the trp mutant, a third TRP-related subunit has previously been proposed to function with TRPL [28].
• We report that anti-INAD antibodies coimmunoprecipitate TRP, identified by its electrophoretic mobility, cross reactivity with anti-TRP antibody, and absence in a null allele trp mutant [29].
• Whole-cell recordings revealed that light-sensitive Ca2+ channels encoded by the trp gene were constitutively active in rdgA photoreceptors [30].
• The trp (transient receptor potential) gene encodes a Ca2+ channel responsible for the major component of the phospholipase C (PLC) mediated light response in Drosophila [19].
• Nucleotide sequence and expression of Escherichia coli trpR, the structural gene for the trp aporepressor [31].

Analytical, diagnostic and therapeutic context of tryptacin

• Despite dramatically different DNA sequence contexts and crystallization conditions, the protein/DNA interface is essentially identical to that seen in the original trp repressor/operator complex structure [17].
• We have shown that MtrB, either from B. subtilis or overexpressed in Escherichia coli, binds specifically to RNA from the leader region of the trp operon by a gel mobility-shift assay [32].
• Results from circular dichroism and UV absorbance spectroscopy support this hypothesis, demonstrating that trp leader RNA becomes unstacked upon binding TRAP [33].
• We found several of the trp family genes were expressed in betaTC3 cells by reverse transcriptase polymerase chain reaction using specific primers, but by Northern blot analysis, mtrp-4 was the predominant message expressed [34].
• Using an enzyme-linked immunosorbent assay to measure antigen-antibody reaction, we found that the binding of L-tryptophan to Trp repressor was associated with a marked decrease in antibody reactivity that presumably accompanied a conformational change in this protein to a state with strong affinity for trp operator-bearing DNA [35].

References