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D C Shaw

Publications and source records attributed to D C Shaw.

At least 73 records · Page 4Linked to original sources
PubMed1982

Adenovirus type 5 induces progression of quiescent rat cells into S phase without polyamine accumulation.

Adenovirus type 5 induces cellular DNA synthesis and thymidine kinase in quiescent rat cells but does not induce ornithine decarboxylase. We now show that unlike serum, adenovirus type 5 fails to induce S-adenosylmethionine decarboxylase or polyamine accumulation. The inhibition by methylglyoxal bis(guanylhydrazone) of the induction of thymidine kinase by adenovirus type 5 is probably unrelated to its effects on polyamine biosynthesis. Thus, induction of cellular thymidine kinase and DNA replication by adenovirus type 5 is uncoupled from polyamine accumulation.

Adenoviruses, Human↗
PubMed1981

In vitro synthesis of the respiratory NADH dehydrogenase of Escherichia coli. Role of UUG as initiation codon.

The respiratory NADH dehydrogenase of Escherichia coli has been synthesized in vitro in a coupled transcription--translation system with cloned deoxyribonucleic acid (DNA) as template. The identity of the protein produced was confirmed by paper chromatography and electrophoresis of tryptic peptides. [35S]Methionine-labeled tryptic peptides from the in vitro product were shown to comigrate with authentic methionine-containing tryptic peptides from the purified enzyme. Using a transcription-translation system derived from an ndh mutant, it was shown that the enzyme produced in vitro was incorporated into membrane vesicles of the mutant to give functional, cyanide-sensitive NADH oxidase activity. Radiochemical N-terminal sequencing of the synthesized NADH dehydrogenase showed that the product was a mixture of three different species, with N-formylmethionine, methionine, or threonine at the N terminus. The results indicated that only partial N-terminal processing was occurring in vitro and that the first residue of the unprocessed NADH dehydrogenase is N-formylmethionine. Since DNA sequencing has shown that this residue is encoded by UUG [Young, I. G., Rogers, B. L., Campbell, H. D., Jaworowski, A., & Shaw, D. C. (1981) Eur. J. Biochem. (in press)], this work verifies the role of UUG as a normal initiation codon.

Amino Acid Sequence↗
PubMed1981

Characterization of the respiratory NADH dehydrogenase of Escherichia coli and reconstitution of NADH oxidase in ndh mutant membrane vesicles.

Highly purified preparations of the cholate-solubilized respiratory NADH dehydrogenase, isolated from genetically amplified Escherichia coli strains [Jaworowski, A., Campbell, H. D., Poulis, M. I., & Young, I. G. (1981) Biochemistry 20, 2041-2047], have been characterized. Enzyme preparations were shown to contain 70% (w/w) lipid, predominantly phosphatidylethanolamine. One mol of noncovalently bound FAD and approximately 1 mol of ubiquinone/mol of enzyme subunit were detected. The purified enzyme was shown to contain only low levels of Fe and acid-labile S, indicating the absence of iron-sulfur clusters. No Cu, Mo, W, or covalently bound P was detected, and no evidence for other chromophores was obtained from visible and ultraviolet absorption spectra of the purified enzyme or of the delipidated polypeptide prepared by gel filtration in sodium dodecyl sulfate. Protein chemical studies verified that the enzyme consists of a single polypeptide species of Mr 47 000, and the N- and C-terminal cyanogen bromide peptides were identified. The pure enzyme was shown to reconstitute membrane-bound, cyanide-sensitive NADH oxidase activity in membrane vesicles prepared from ndh mutant strains.

Amino Acids↗
PubMed1981

Porcine beta-lactoglobulin A and C. Occurrence, isolation and chemical properties.

The occurrence of the dominant 'whey' protein in samples of milk from 1180 sows is examined. It exhibits genetic polymorphism with some unusual features. Although immunologically different from bovine beta-lactoglobulin, it is shown by chemical studies of the isolated protein to be a beta-lactoglobulin. Two homozygous genetic variants, designated porcine beta-lactoglobulin A and C, are isolated and their amino acid compositions and peptide maps compared. It is shown that the C variant has +1 His, -1 Gln, and +1 Asp, -1 Glu, with respect to the A variant. These variants, containing ca. 162 residues per molecule, are considered in relationship to porcine beta-lactoglobulins isolated by other workers. The sequence of the first 50 residues is determined and compared with the sequence of the bovine protein. The sequences of ca. 70% of the remaining residues is proposed on the basis of the composition of tryptic peptides and assumed homology.

Amino Acid Sequence↗
PubMed1981

Porcine alpha-lactalbumin A and B.

The occurrence of the 'whey' protein, alpha-lactalbumin, in pig (Sus scrofus) milk samples from 904 sows is examined. A semi-discontinuous buffer system has been developed to detect the existence of genetic polymorphism. There are two homozygous variants, designated A and B. Both variants are isolated and it is shown by peptide and sequencing studies that the A variant differs from the B variant by having an Arg residue substituted for the Lys residue at the N-terminus of the molecule. The sequence of the first thirty residues is determined and compared with those of related alpha-lactalbumins.

Amino Acid Sequence↗
PubMed1981

Nucleotide sequence coding for the respiratory NADH dehydrogenase of Escherichia coli. UUG initiation codon.

The nucleotide sequence of the structural gene coding for the respiratory NADH dehydrogenase of Escherichia coli has been determined by the chain-termination method. The reading frame for the protein starts with the unusual initiation codon UUG and predicts an amino acid sequence of 434 residues (Mr = 47 304). The reading frame was confirmed by protein chemical studies including determination of the N-terminal sequence of the protein. The product made in vivo was found to have threonine as its N-terminal residue, indicating that the initiating N-formylmethionine had been removed by post-translational processing.

Amino Acid Sequence↗
PubMed1981

Eosinophilic cystitis.

Eosinophilic cystitis is an uncommon inflammatory disease of the urinary bladder characterized by irritative urinary symptoms and eosinophilia of the involved tissue and often of the peripheral blood. Parasitic bladder infiltration has been suggested as the etiologic agent, but review of the literature revealed only one case in which this was proven. A 3.5-year-old boy with eosinophilic cystitis was extensively investigated, but there was no evidence of parasitism. Several immunologic reactions may cause eosinophilia in both tissues and peripheral blood, but no specific allergen could be found in this patient.

Adolescent↗
PubMed1980

Comparative studies of alpha-lactalbumin and lysozyme: the proteins of kangaroo (Megaleia rufa and Macropus giganteus) and horse (Equus caballus).

As part of a study of the 'whey' proteins of various mammals, a comparison is made of the alpha-lactalbumins and lysozymes of the kangaroo and horse. In the milk of the red kangaroo (Megaleia rufa) there is only one alpha-lactalbumin and it occurs throughout lactation, but no lysozyme has been detected. There are two alpha-lactalbumins in the milk of the grey kangaroo (Macropus giganteus), one, designated alpha-lactalbumin Zone B, is present throughout lactation; the second, designated alpha-lactalbumin Zone A, is present only in late lactation. One lysozyme is also present. The milk of the horse (Equus caballus) contains one alpha-lactalbumin and at least one lysozyme. Partial amino acid sequences are proposed from sequence determination and from analyses of tryptic peptides compared with the known sequences of other alpha-lactalbumins and lysozymes.

Amino Acid Sequence↗
PubMed1980

Nature of the heterogeneity within genetic variants of bovine serum transferrin.

A comparison is made of the four main components of an homozygous variant (A or D2D2) of bovine serum transferrin. These are designated I-IV in order of increasing mobility in electrophoresis at pH 7.5. Components I, II, III and IV have 2,2,3 and 3 residues of sialic acid per transferrin molecule and appear to correspond to components 2a, 2b, 3a and 3b respectively of Stratil & Spooner (1971). The difference between components I and II and between III and IV does not reside in sialic acid differences. On the basis of peptide maps of reduced carboxamidomethylated components, urea-starch gel electrophoresis and quantitative sequence studies, it is concluded that components II and IV have a scission in the peptide chain. By homology with the sequency of MacGillivray et al. (1977) for human serum transferrin it is suggested that the scission occurs between residues 55 and 54 from the C-terminus and this portion of the chain has a 'molecular' weight of ca. 6000. The implications are briefly discussed.

Amino Acid Sequence↗
PubMed1978

Hemocyanin from the Australian freshwater crayfish Cherax destructor. Characterization of a dimeric subunit and its involvement in the formation of the 25S component.

The molecular weight of a dimeric subunit, M3', isolated from Cherax destructor hemocyanin has been measured by sedimentation equilibrium to be 144 000. Peptide mapping and end-group analysis together with gel electrophoresis show that the dimer consists of two very similar or identical monomers, cross-linked by disulfide bridges. Dissociation of the 25S component of the hemocyanin shows that it contains the dimer and two previously identified monomers, M1 and M2. Its molecular weight is 900 000 by sedimentation equilibrium, and reconstitution studies show that the dimer is essential for its formation. Analysis of the results of polyacrylamide disc gel electrophoresis experiments with the 25S component indicates that it consists of a population of 11 compositional isomers. These all contain one dimeric subunit and ten monomeric subunits, the latter being present in all the combinations of M1 and M2.

Amino Acids↗
PubMed1978

The amino acid sequence of cytochrome c from the blowfly Lucilia cuprina.

The amino acid sequence of cytochrome c isolated from the sheep blowfly Lucilia cuprina has been determined by comparison of the compositions of the tryptic peptides to those predicted from the published sequences of cytochromes c from other insects. Cytochrome c from L. cuprina differs at a single residue when compared to cytochrome c from the screw worm fly Haematobia irritans, a species belonging to the same order as the blowfly. This substitution, proline for alanine, has been located at position 44 in the protein chain.

Amino Acid Sequence↗
PubMed1976

The structure of human thrombin in relation to autolytic degradation.

Human thrombin was obtained by activation of human prothrombin with venom of the Australian Taipan (Oxyuranus scutellatus scutellatus). This thrombin was precipitated with ammonium sulphate (75% saturation) and subsequently purified by gel-filtration (Sephadex G-75), ion-exchange (CM-Sephadex C-50) and affinity (aminobenzamidine-CH-Sepharose) chromatography. The final preparation (affinity thrombin) had a specific activity of 2340 Iowa units per absorbance unit (A1cm280). Thrombin proteins focused between 5 and 7, while prothrombin proteins focused to pH values less than 5. SDS-acrylamide gel electrophoresis indicated molecular weights of greater than 70 000 for prothrombin and 39 000, 28 000, 25 000-23 000 and 15 000-13 000 for affinity thrombin proteins. The 39 000-dalton species predominated (greater than 90%) when the enzyme was inhibited with phenylmethanesulphonyl fluoride prior to dialysis for SDS electrophoresis. Lack of such inhibition reduced the amount of the 39 000-dalton species to less than 60% with concomitant increase of the smaller species. Peptide mapping studies indicated that the smaller species were structurally related to the 39 000-dalton species. The amino acid compositions of the histidine and/or tyrosine containing peptides indicated a high degree of homology with bovine thrombin. It has been established that human thrombin can exist in at least two secondary structural forms, of different molecular weights, probably due to autolytic degradation of the largest (39 000-dalton) form.

Amino Acid Sequence↗
PubMed1976

Genetics of lucilin, a storage protein from the sheep blowfly, Lucilia cuprina (Calliphoridae).

Lucilin, the main storage protein of larval fat body and hemolymph in the sheep blowfly, Lucilia cuprina, has been isolated as a series of trimers composed of subunits of 83,000 +/- 5%, daltons. Extensive electrophoretically detectable polymorphism of lucilin subunit patterns occurs in wild and laboratory populations of Lucilia; from four to nine bands are seen in any one individual. Evidence from genetic, electrophoretic, immunological, and structural studies suggests the existence of a series of 12 or more closely related structural loci (designated Luc-1 to Luc-12) which may have arisen through gene duplication. Codominant allelic variation has been found at several of these loci. Luc-1 and Luc-3, and probably the other structural loci of the series, are located on chromosome 2.

Adipose Tissue↗
PubMed1976

In vitro translation of polyribosome-associated RNAs from tobamovirus-infected plants.

RNAs associated with polyribosomes in plants infected with the U2 strain of tobacco mosaic virus (TMV) or with sunnhemp mosaic virus have been isolated. Most are about 0.35 X 10(6) daltons in weight. They translate efficiently in vitro to produce their respective coat proteins which were identified by their serological behavior and peptide composition. They also reassemble in vitro with coat protein. The coat protein of sunnhemp mosaic virus reassembles more quickly than that of TMV U2.

Cell-Free System↗