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S J Stanley

Publications and source records attributed to S J Stanley.

34 records · Page 2Linked to original sources
PubMed1983

Amino acid-specific ADP-ribosylation.

[adenine-U-14C]ADP-ribose-agmatine and [adenine-U-14C ))ADP-ribose-histone were synthesized by an NAD:arginine ADP-ribosyltransferase from [14C]NAD and agmatine and histone, respectively. The pseudo-first order rate constants for breakdown of the two components either in 0.4 N NaOH or in 0.4 M neutral hydroxylamine were identical. Hydroxylamine treatment of [14C]ADP-ribose-agmatine or [32P]ADP-ribose-histone yielded a single radioactive product which was separated by high pressure liquid chromatography and identified as ADP-ribose-hydroxamate by the formation of a ferric chloride complex. Hydrolysis of ADP-ribose-hydroxamate with snake venom phosphodiesterase resulted in the formation of 5'-AMP, consistent with the presence of a pyrophosphate bond. Incubation of ADP-ribose-[14C]agmatine, synthesized by the ADP-ribosyltransferase from NAD and [14C]agmatine, with 0.4 M neutral hydroxylamine resulted in the release of [14C]agmatine rather than phosphoribosyl[14C]agmatine. In addition, neither NAD nor ADP-ribose reacts with hydroxylamine; i.e. there was no evidence of nucleophilic attack by hydroxylamine at the pyrophosphate bond. The ADP-ribosyl-protein linkage formed by the NAD:arginine ADP-ribosyltransferase is considerably more stable to hydroxylamine than is the ADP-ribose-glutamate bond. The presence of ADP-ribose-arginine and ADP-ribose-glutamate synthesized by the ADP-ribosyltransferase and poly(ADP-ribose) synthetase, respectively, may be the chemical basis for the "hydroxylamine-stable" and "hydroxylamine-labile" bonds described by Hilz (Hilz, H. (1981) Hoppe-Seyler's Z. Physiol. Chem. 362, 1415-1425).

ADP Ribose Transferases↗
PubMed1983

Airborne contamination of wounds in joint replacement operations: the relationship to sepsis rates.

During operations for total joint replacement done in operating rooms with conventional ventilation the mean air contamination varied considerably among the 15 hospitals studied. The range was from 51 to as many as 539 bacteria-carrying particles per cubic metre. When the data from all the hospitals were grouped according to the mean level of bacterial airborne contamination, including operations done in control and in ultraclean air, there was a good correlation between the air contamination and the joint sepsis rate. There was also a correlation between the mean values of air contamination and the numbers of bacteria isolated from wound wash-out samples; but the apparent efficiency of the sampling method varied a great deal among the hospitals carrying out this procedure. From this data it would seem that by far the largest proportion of bacteria found in the wound after the prosthesis had been inserted reached it by the airborne route. With the mean air contamination found in the control series, 164 bacteria-carrying particles per cubic metre, this proportion was as much as 95 per cent. The risk of joint sepsis varied widely among the 19 hospitals. The differences between the highest and lowest being probably as much as 20-fold. However, the effect of an ultraclean air environment was asimilar at all hospitals.

Air Microbiology↗
PubMed1983

Bacteria isolated from deep joint sepsis after operation for total hip or knee replacement and the sources of the infections with Staphylococcus aureus.

A wide variety of bacterial species, many usually regarded as of low pathogenicity, were isolated from septic joints after operation for total hip or knee joint replacement in a multi-centre trial of ultraclean air in operating rooms. The prophylactic antibiotics generally used appeared to reduce considerably the rates of infection with most species but to be ineffective against 'gut' organisms. For about half the septic infections involving Staphylococcus aureus nasal swabs had been obtained from the patient and operating staff at the time of operation for insertion of the prosthesis. Strains of Staph, aureus isolated from these and from the infected joints were phage typed and tested for antibiotic sensitivity. A probable source among the carriers was found for seven out of the 14 infections and a possible source for another five. Very small numbers of Staph. aureus were needed to initiate infection.

Air Microbiology↗
PubMed1982

Effect of ultraclean air in operating rooms on deep sepsis in the joint after total hip or knee replacement: a randomised study.

In a multicentre study of sepsis after total hip or knee replacement the operations performed by each surgeon were allocated at random between control and ultraclean-air operating rooms. Records were obtained from over 8000 such operations. In the patients whose prostheses were inserted in an operating room ventilated by an ultraclean-air system the incidence of joint sepsis confirmed at reoperation within the next one to four years was about half that of patients who had had the operation in a conventionally ventilated room at the same hospital. When whole-body exhaust-ventilated suits had been worn by the operating team in a theatre ventilated by an ultraclean-air system the incidence of sepsis was about a quarter of that found after operations performed with conventional ventilation. When all groups in the trial were considered together the analysis showed deep sepsis after 63 out of 4133 operations in the control group (1.5%) and after 23 out of 3922 operations in the ultraclean-air groups (0.6%) (ratio 2.6, 95% confidence limits 1.6-4.2; p less than 0.001). The design of the study did not include a strictly controlled test of the effect of prophylactic antibiotics, but their use was associated with a lower incidence of sepsis than in patients who had received no antibiotic prophylaxis at their operations (0.6% (34/5831) v 2.3% (52/2221); ratio 4.0).

Air Microbiology↗
PubMed1982

Activation of an NAD:arginine ADP-ribosyltransferase by histone.

An ADP-ribosyltransferase from turkey erythrocytes which utilizes proteins and low molecular weight guanidino compounds such as arginine and agmatine as ADP-ribose acceptors was stimulated by histones. The effect was specific in that choleragen, a bacterial mono(ADP-ribosyl)transferase that increased adenylate cyclase activity in animal cells, was not activated by histones. With the erythrocyte enzyme, histones decreased the apparent Km values for arginine methyl ester and agmatine and increased the stability of the transferase to thermal denaturation. Activation of the transferase by histones was rapid, with a minimal delay observed upon addition of histones to a histone-free assay. Activation by histones was reversed upon dilution of a sample containing histones into an assay mix free of histone. In the absence of histone, the transferase existed as a rapidly sedimenting species; in the presence of histone, the transferase sedimented as a protomer.

ADP Ribose Transferases↗
PubMed1981

Amino acid-specific ADP-ribosylation. Identification of an arginine-dependent ADP-ribosyltransferase in rat liver.

A partially purified protein preparation from rat liver catalyzed the ADP-ribosylation of low molecular weight guanidino compounds and proteins. Agmatine and arginine, previously shown to be effective acceptors for the guanidine-dependent erythrocyte ADP-ribosyltransferase, were used as acceptors by the rat liver enzyme; lysine, histidine, and serine were inactive. The product of the reaction between [adenine-U-14C]NAD and agmatine catalyzed by the rat liver enzyme co-chromatographed with [adenine-U-14C]ADP-ribose-agmatine which was synthesized by the erythrocyte transferase; in parallel assays, formation of this product was associated with stoichiometric release of [carbonyl-14C]nicotinamide from [carbonyl-14C]NAD. In the presence of histones or other proteins and [adenine-U-14C]NAD or [32P]NAD, the rat liver enzyme catalyzed the formation of a radioactive product which was precipitable by trichloroacetic acid. Digestion of the [adenine-U-14C]-labeled precipitate with snake venom phosphodiesterase released a labeled compound identified as 5'-AMP. These data are consistent with the conclusion that a mono-(ADP-ribosyltransferase) is present in rat liver which utilizes guanidino compounds such as arginine as ADP-ribose acceptors. The ADP-ribose-glutamate bond has been shown to exist in rat liver. Since the catalytic sites of each transferase can accommodate and thus ADP-ribosylate only one specific amino acid, a family of site-specific transferases must be present. The availability of multiple site-specific transferases permits the cell to exert further control over ADP-ribosylation.

ADP Ribose Transferases↗
PubMed1981

BCG vaccination of children against leprosy in Uganda: final results.

A total of 19 200 children, all contacts or relatives of known leprosy patients, and all free of visible leprosy lesions, were included in a controlled trial of BCG vaccination against leprosy in Uganda between 1960 and 1964. They were followed for an average of 8 years, during which time 261 developed early leprosy lesions. A less comprehensive follow-up was carried out for a further 5 years, when 8 more cases of leprosy were identified.In the main intake, between 1960 and 1962, 16 150 tuberculin-negative or weakly tuberculin-positive (Heaf Grades O-II) children were allocated by an effectively random process to either a BCG-vaccinated or an unvaccinated control group. Both groups were seen and examined in an identical fashion for leprosy at approximately 2-year intervals, and precautions were taken to ensure unbiased assessment of new cases of leprosy. After 8 years, 41 cases of leprosy had been identified in the BCG-vaccinated group, and 201 in the control group, a percentage reduction in the BCG-vaccinated group compared with the control group of 80%. The percentage reduction was similar for those initially tuberculin-negative, and for those initially weakly positive, and did not depend upon the age at vaccination. It was also similar for both sexes, for contacts of lepromatous and contacts of non-lepromatous leprosy, for children having contact with one or more than one patient, and for differing grades of physical contact and genetic relationship with a patient. The protective effect of BCG vaccination continued over the 8-year period, although it may have fallen off slightly at the end.In a group of 1074 strongly tuberculin-positive (Heaf Grades III-IV) children followed in parallel with the other two groups a total of 16 cases of leprosy were identified. When adjusted for age, this incidence is 58% lower than that in the unvaccinated control children who were initially tuberculin-negative, indicating a protective effect against leprosy of naturally-acquired strong tuberculin sensitivity.Between 1970 and 1975, one new case of leprosy was identified in a child who had initially been strongly tuberculin-positive and had therefore not been vaccinated, one in a BCG-vaccinated child, and 6 in control children. Although the follow-up in this period was less comprehensive than that in the main part of the trial, the ascertainment of cases was unlikely to have been biased towards either vaccinated or control children. These results indicate a continuing protective effect of BCG up to 12-13 years after vaccination.

Adolescent↗
PubMed1981

Histone-dependent and histone-independent forms of an ADP-ribosyltransferase from human and turkey erythrocytes.

An ADP-ribosyltransferase from turkey erythrocytes, which catalyzes the mono(ADP-ribosylation) of guanidino compounds such as arginine and of many purified and crude cellular proteins, appears to exist both in high-activity, histone-independent and low-activity, histone-dependent forms. At low salt concentrations, the activity of the transferase with agmatine as acceptor was less than 10% that observed in the presence of 200 mM NaCl. In the absence of salts, ADP-ribosylation of agmatine was stimulated greater than 10-fold by histones, and activity approached that observed with high salt concentration; under these conditions, the histones did not serve as ADP-ribose acceptors themselves. Histone also activated the highly purified ADP-ribosyltransferase from human erythrocytes. Enzyme activity was increased in the presence of salt and was then relatively independent of histones. DNA was not required for the stimulation of ADP-ribosylation by histone; incubation of the transferase and histone with DNase did not significantly decrease enzymatic activity. Additional DNA in the assay decreased the effect of histone. The erythrocyte ADP-ribosyltransferase from diverse species thus appears to exist in two forms: one is dependent on histones for activity and one which, in the presence of salt, has high intrinsic activity and is independent of histone. The fact that the active forms of the transferase generated in the presence of salt or histone have similar catalytic activity suggests that these forms of transferase may be identical. It would appear that the enzymatic activity of transferase from different species may be controlled by histones.

ADP Ribose Transferases↗
PubMed1980

Activation of choleragen by thiol: protein disulfide oxidoreductase.

In the presence of thiols such as glutathione or dithiothreitol, choleragen catalyzes the NAD-dependent ADP-ribosylation of arginine and proteins; thiols reduce the disulfide linking the A1 and A2 peptides of the A protomer of the toxin, releasing the active A1 peptide. Homogeneous thiol:protein disulfide oxidoreductase from bovine liver, in the presence of limiting concentrations of glutathione or dithiothreitol, increased the rate of activation of choleragen and its A protomer. The ability of oxidoreductase preparations to activate choleragen co-chromatographed with oxidoreductase protein on gel permeation columns and was proportional to the concentration of oxidoreductase in the assay. In the presence of oxidoreductase, the concentrations of glutathione and dithiothreitol necessary for activation were reduced. Thiol:protein disulfide oxidoreductase could play a role in the reduction of choleragen and release of the catalytically active A1 peptide.

Animals↗
PubMed1980

ADP-ribosyltransferase activity of mono- and multi-(ADP-ribosylated) choleragen.

Choleragen (cholera toxin) catalyzed the NAD-dependent auto-ADP-ribosyltation of its A1 peptide. The number of ADP-ribose moieties incorporated into ech A1 peptide was dependent on incubation conditions and time as well as toxin concentration. There was no evidence for the formation of poly(ADP-ribosylated) toxin. The formation of mono- and multi-(ADP-ribosylated) A1 peptides was prevented by the addition of arginine, an alternative ADP-ribose acceptor. Triton X-100 polyacrylamide gel electrophoresis separated the A1 peptide of choleragen from the B complex and multi-(ADP-ribosylated) A1 peptides from unmodified A1. The A1 peptides ADP-ribosylated in the presence of [32P]NAD contained approximately 1, 2, or 3 ADP-ribose molecules/23,500-dalton units; under the conditions used for electrophoresis, the mobilities of the A1 peptides were enhanced by incorporation of ADP-ribose. The mono- and multi-(ADP-ribosylated) A1 peptides catalyzed the NAD-dependent ADP-ribosylation of arginine methyl ester. The turnover numbers of the mono- and multi-(ADP-ribosylated) A1 peptides were consistently 30 to 50% higher than that of the A1 peptide from native toxin.

Adenosine Diphosphate Ribose↗
PubMed1980

Isolation and properties of an NAD- and guanidine-dependent ADP-ribosyltransferase from turkey erythrocytes.

An NAD- and guanidine-dependent ADP-ribosyltransferase has been purified more than 500,000-fold from turkey erythrocytes with an 18% yield. The enzyme in the 100,000 X g supernatant fraction was bound to phenyl-Sepharose, eluted with 50% propylene glycol, and further purified by sequential chromatographic steps on carboxymethylcellulose, NAD-agarose and concanavalin A-agarose. The transferase was specifically eluted from concanavalin A-agarose with alpha-methylmannoside. The enzymatic activity was extremely labile following the first purification step. Both propylene glycol and NaCl stabilized the transferase; significant increases in enzyme recovery were obtained by conducting the NAD- and concanavalin A-agarose chromatography in buffer containing propylene glycol. The purified protein exhibits one predominant protein band on SDS-polyacrylamide gels with an estimated molecular weight of 28,300. On Ultrogel AcA54 chromatography, single coincident peaks of ADP-ribosyltransferase activity and protein were observed. Enzyme activity was independent of DNA; the highly purified transferase was inhibited by thymidine, nicotinamide, and theophylline. The specific activity of the purified enzyme (350 mumol of ADP-ribose transferred from NAD to arginine methyl estermin-1mg-1) is comparable to that reported for purified NAD glycohydrolases and poly(ADP-ribosyl)transferases.

Animals↗