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C Binnie

Publications and source records attributed to C Binnie.

27 records · Page 2Linked to original sources
PubMed1989

Cloning and heterologous expression in Streptomyces lividans of Streptomyces rimosus genes involved in oxytetracycline biosynthesis.

The anhydrotetracycline (ATC) oxygenase enzyme which carries out the conversion of ATC to dehydrotetracycline was purified and the N-terminal amino acid sequence was determined. The sequence displays a significant similarity to that of the p-hydroxybenzoate hydroxylase from Pseudomonas fluorescens. This is consistent with the activity of the oxygenase, i.e., addition of a hydroxyl moiety to an aromatic ring structure. Oligonucleotide probes were designed and used to clone the corresponding fragment of chromosomal DNA from Streptomyces rimosus. This DNA fragment was used to screen a cosmid library, allowing the isolation of flanking DNA sequences. Surprisingly, the gene was located within the previously cloned cluster of genes involved in the synthesis of the biosynthetic intermediate ATC and not as had been expected (P. M. Rhodes, N. Winskill, E. J. Friend, and M. Warren, J. Gen. Microbiol. 124:329-338, 1981) at a separate locus on the other side of the chromosome. Subcloning of an appropriate DNA fragment from one of the cosmid clones onto pIJ916 produced Streptomyces lividans transformants which synthesized oxytetracycline.

Amino Acid Sequence↗
PubMed1988

Cloned gene encoding the delta subunit of Bacillus subtilis RNA polymerase.

Core RNA polymerase and several forms of RNA polymerase holoenzyme from Bacillus subtilis are found in association with a 21,500-kDa polypeptide called delta (delta). We have cloned the structural gene (rpoE) for delta by using a hybridization probe a synthetic oligodeoxynucleotide that was designed on the basis of a partial NH2-terminal amino acid (aa) sequence of purified delta protein. The rpoE gene was found to encode a 173-aa polypeptide of a predicted Mr of 20,400. Genetic and physical mapping experiments placed rpoE at 325 degrees on the B. subtilis chromosome and established the gene order rpoE-ctrA-spo0F. The delta subunit is known to enhance the specificity of transcription in vitro by bacterial and phage SP01-modified forms of polymerase, but replacement of rpoE by an in vitro-constructed deletion-mutated gene was found not to impair viability, sporulation, or the growth of phage SP01.

Amino Acid Sequence↗
PubMed1987

Hearing words and seeing colours: an experimental investigation of a case of synaesthesia.

A case of 'chromatic-lexical' (colour-word) synaesthesia is described, and its genuineness confirmed using the criterion of stable cross-modality imagery across time. The synaesthesia could not be accounted for by a memory hypothesis, nor was it associated with any psychiatric condition. Further analysis did not identify any semantic relationship between real words and colours, but the colours of nonwords were determined by the colours of the individual letters. Numbers also had their own stable colours. The experience of synaesthesia was triggered by other auditory stimuli, but most strongly by words. Cortical electrophysiological recording failed to reveal any abnormalities. An unusual organisation of modalities in the brain is postulated to account for the phenomenon.

Aged↗
PubMed1986

Gene encoding the sigma 37 species of RNA polymerase sigma factor from Bacillus subtilis.

sigma 37 is a minor species of RNA polymerase sigma factor found in the Gram-positive bacterium Bacillus subtilis. sigma 37 governs the transcription in vitro of genes that are turned on at an early stage in spore formation, as well as other genes that are switched on at the end of the exponential phase of growth but that are not under sporulation control. To study the role of sigma 37 in B. subtilis gene expression, we have cloned the gene for this minor species of sigma factor in Escherichia coli by using as a hybridization probe a synthetic oligonucleotide that was designed on the basis of the NH2-terminal amino acid sequence of sigma 37 protein. We determined the nucleotide sequence of the entire sigma 37 gene, which was found to encode a 262-amino acid residue polypeptide of 29.9 kDa. The predicted amino acid sequence of sigma 37 showed significant homology to that of other sigma proteins in a region that has been proposed to be the site of binding of these factors to core RNA polymerase. Genetic mapping experiments placed the gene for sigma 37, herein designated sigB, at 40 degrees on the genetic map of Piggot and Hoch [Piggot, P. & Hoch, J. A. (1985) Microbiol. Rev. 49, 158-179]. An insertion mutation was constructed in sigB and found not to impair growth or sporulation.

Amino Acid Sequence↗
PubMed1986

Tolerance to bromodeoxyuridine in a thymidine-requiring strain of Bacillus subtilis.

Mutations which allow tolerance to 5-bromo-2'-deoxyuridine (BUdR) in a thymidine (TdR)-requiring strain of Bacillus subtilis have been examined. Differences in sensitivity to BUdR existed between isogenic strains harbouring the mutations. Those mutations originally isolated as BUdR-tolerant also bestowed tolerance to 5-bromouracil and vice versa. The strain exhibiting the greatest tolerance to BUdR maintained a normal rate of replication in the presence of BUdR whereas the parent strain did not, but the tolerant strain incorporated less analogue into DNA than the parent strain. The basis of the tolerance mutation appeared to lie at the point of uptake of the analogue into the cell as the tolerant mutant preferentially took up TdR over BUdR into whole cells. DNA polymerase activity measured in vitro did not distinguish between TdR and BUdR in either the parent or the mutant strain and although TdR kinase activity showed a preference for TdR over BUdR as a substrate, the extent of discrimination was similar in both strains.

Bacillus subtilis↗
PubMed1986

Inhibition of sporulation in Bacillus subtilis by bromodeoxyuridine and the effect on DNA replication.

A 5-bromo-2'-deoxyuridine (BUdR)-tolerant derivative of a thymidine (TdR)-requiring strain of Bacillus subtilis was used to examine the effect of BUdR, an analogue of TdR, on sporulation. At a TdR:BUdR ratio which had little effect on growth, sporulation was inhibited if cells were exposed to BUdR during the period of DNA synthesis at the onset of the process. Cells recovered from BUdR inhibition of sporulation if the analogue was removed and DNA replication allowed to continue with TdR alone. BUdR prolonged the period of DNA synthesis during sporulation and experiments with chloramphenicol suggested that this was due in part to unscheduled initiation of new rounds of replication.

Bacillus subtilis↗
PubMed1985

Parallel characterization of bovine von Willebrand protein (factor VIII-associated protein) by light scattering and SDS gel electrophoresis.

Highly purified bovine von Willebrand protein (vWP) has been studied with two complementary techniques. Light scattering measurements on different samples give weight average molecular weights in the range from 7 to 13 million, radius of gyration between 75 and 140 nm and diffusion coefficient near 4.15 X 10(-8) cm2/sec. Scans after electrophoresis in sodium dodecyl sulfate on 2% agarose gels, stained with Coomassie blue, allow calculation of a mass distribution over a series of oligomers with relative size in a range from 1 to 20. The ratio of the average mol. wt. from light scattering and the average size for the observed distribution, which is the mol. wt. increment for successive vWP oligomers, has been determined and found to be 1.0 million. This implies that the molecules of vWP are oligomers of subunits themselves consisting of 4 polypeptide chains each of mol. wt. circa 250,000.

Animals↗
PubMed1983

Density gradient analysis of DNA replicated during Bacillus subtilis sporulation.

Density gradient centrifugation was used to monitor DNA replication during sporulation of a 5-bromo-2'-deoxyuridine-tolerant, thymidine-requiring strain of Bacillus subtilis. DNA of heavy, intermediate, and light density was found in cells induced to sporulate in the presence of bromodeoxyuridine, but only intermediate DNA was detected in mature spores. Cells grown with bromodeoxyuridine until DNA was in the heavy form formed spores containing intermediate and light DNA when sporulated with thymidine alone.

Bacillus subtilis↗