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Scott AI. Wie die Natur Vitamin B12 synthetisiert – ein Überblick über die letzten vier Milliarden Jahre. Angew Chem Int Ed Engl 1993. [DOI: 10.1002/ange.19931050904] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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127
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Scott AI. How Nature Synthesizes Vitamin B12?A Survey of the Last Four Billion Years. ACTA ACUST UNITED AC 1993. [DOI: 10.1002/anie.199312233] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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128
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Ahmed AA, Mahmoud AA, Williams HJ, Scott AI, Reibenspies JH, Mabry TJ. New sesquiterpene alpha-methylene lactones from the Egyptian plant Jasonia candicans. JOURNAL OF NATURAL PRODUCTS 1993; 56:1276-1280. [PMID: 8229012 DOI: 10.1021/np50098a011] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Extracts of the plant Jasonia candicans possess antimicrobial activity. ET2O/MeOH extracts were subjected to liquid chromatography, and several sesquiterpenes were isolated and identified including the known compounds confertin [1], 4,11(13)-eudesmadien-12-oic acid [2], and 11-eudesmen-4-ol [3]. Two new diol alpha-methylene lactone antimicrobial agents were identified from nmr and mass spectral data and X-ray crystallography as (4 alpha, 5 alpha, 8 beta, 10 beta)-4,10-dihydroxy-1,11(13)-guaidien-12,8-olide [4] and (4 alpha, 5 alpha, 8 beta, 10 alpha)-4,10-dihydroxyl-1,11 (13)-guaidien-12,8-olide[5], which differ in stereochemistry at the C-10 tertiary alcohol center.
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Scott AI, Whalley LJ. The onset and rate of the antidepressant effect of electroconvulsive therapy. A neglected topic of research. Br J Psychiatry 1993; 162:725-32. [PMID: 8330103 DOI: 10.1192/bjp.162.6.725] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
This annotation is concerned with how soon and at what rate antidepressant effects become apparent over a course of electroconvulsive therapy (ECT). The first question is of importance in the design and interpretation of biological studies of the mode of action of ECT. The second question is of practical interest to the treating psychiatrist when we ask how the speed of recovery is influenced by what the psychiatrist prescribes, that is, the number and frequency of treatments. These questions are little better answered now than 20 years ago. This may come as a surprise to many readers, who have been advised to use ECT when “seeking rapid improvement” in depressive disorders (ECT Sub-Committee of the Research Committee of the Royal College of Psychiatrists, 1989). This lack of progress is attributable to a dearth of appropriately designed ECT studies.
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Riddle WJ, Scott AI, Bennie J, Carroll S, Fink G. Current intensity and oxytocin release after electroconvulsive therapy. Biol Psychiatry 1993; 33:839-41. [PMID: 8373922 DOI: 10.1016/0006-3223(93)90026-a] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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131
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Roessner CA, Min C, Hardin SH, Harris-Haller LW, McCollum JC, Scott AI. Sequence of the Candida albicans erg7 gene. Gene 1993; 127:149-50. [PMID: 8486282 DOI: 10.1016/0378-1119(93)90631-c] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The nucleotide sequence of the Candida albicans erg7 gene, which complements erg7 mutants of Saccharomyces cerevisiae and restores oxidosqualene cyclase activity, was determined. The gene encodes a 728-aa protein that displays homology with squalene-hopene cyclase, providing further evidence that erg7 is the gene encoding 2,3-oxidosqualene cyclase.
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132
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Moore M, Narasimhan TR, Wang X, Krishnan V, Safe S, Williams HJ, Scott AI. Interaction of 2,3,7,8-tetrachlorodibenzo-p-dioxin, 12-O-tetradecanoylphorbol-13-acetate (TPA) and 17 beta-estradiol in MCF-7 human breast cancer cells. J Steroid Biochem Mol Biol 1993; 44:251-61. [PMID: 8384872 DOI: 10.1016/0960-0760(93)90085-b] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) and 12-O-tetradecanoylphorbol-13-acetate (TPA) are both tumor promoters which act through different mechanisms. In MCF-7 human breast cancer cells, both TCDD and TPA inhibited constitutive and 17 beta-estradiol-induced cell proliferation but showed no apparent interactive effects. TCDD also inhibited the 17 beta-estradiol-induced secretion of the 52-kDa protein (procathepsin D) and induced CYP1A1 gene expression whereas TPA alone was inactive for these responses. Moreover, TPA did not modulate the TCDD-mediated antiestrogenic or induction responses and did not decrease levels of the nuclear Ah receptor complex as determined in a gel mobility shift assay using a 32P-dioxin responsive element (DRE). The interactions of TPA and TCDD on the metabolism of [13C]glucose to [13C]lactate was also investigated using 13C-nuclear magnetic resonance spectroscopy. The rate of formation of [13C]lactate from [13C]glucose in MCF-7 cells treated with DMSO (control), 1 nM 17 beta-estradiol, 1 nM TCDD, 1 nM TCDD plus 1 nM 17 beta-estradiol, and 0.1 ng/ml TPA plus 1 nM 17 beta-estradiol was 28, 48, 20, 22 and 50 fmol lactate formed/cell/h, respectively. Thus, TCDD, but not TPA, inhibited this estrogen-induced response. However, a comparison of the rate of lactate formation in cells treated with TCDD plus 17 beta-estradiol (22 fmol/cell/h) or TCDD plus 17 beta-estradiol plus TPA (61 fmol/cell/h) showed that TPA significantly inhibited the TCDD-mediated antiestrogenic response. The results of these studies in MCF-7 cells demonstrate that the interactions of TCDD and TPA are highly response-specific and do not involve TPA-mediated downregulation of the nuclear Ah receptor complex.
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Roessner CA, Devagupta R, Hasan M, Williams HJ, Scott AI. Purification of an indole alkaloid biosynthetic enzyme, strictosidine synthase, from a recombinant strain of Escherichia coli. Protein Expr Purif 1992; 3:295-300. [PMID: 1330135 DOI: 10.1016/1046-5928(92)90004-g] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The gene for the indole alkaloid biosynthetic enzyme, strictosidine synthase, of Catharanthus roseus has been cloned into an inducible Escherichia coli expression vector using an expression cassette polymerase chain reaction technique. Induction of the gene resulted in overexpression of the enzyme which accumulated mainly as insoluble inclusion bodies. Denaturation and refolding of the insoluble protein resulted in the ability to purify up to 6 mg of active enzyme from a single liter of cell culture. The recombinant enzyme has good activity (approximately 30 nkat/mg).
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McCaskill D, Scott AI. Visualization of vacuoplasts in isolated vacuole preparations from mesophyll protoplasts of periwinkle [Catharanthus roseus (L.) G. Don]. PLANT CELL REPORTS 1992; 11:310-313. [PMID: 24203146 DOI: 10.1007/bf00235088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/1992] [Revised: 03/20/1992] [Indexed: 06/02/2023]
Abstract
A procedure was developed for the rapid detection of vacuoplasts in vacuole preparations isolated from mesophyll protoplasts of Catharanthus roseus (L.) G. Don (periwinkle). The procedure relies on the staining of surface carbohydrates on the plasma membrane surrounding vacuoplasts with fluorescein-labeled lectins. When isolated under conditions of constant osmotic strength, approximately 15-20% of the vacuoles isolated showed surface labeling with FITC-agglutinin from Abrus precatorius. Isolation of vacuoles after an initial osmotic shock showed much lower (<5%) surface labeling. This lower level of surface labeling correlated well with a lower level of other non-vacuolar marker enzyme activities. A thin layer of cytoplasm was visible in a small number of these stained structures, indicating that they were vacuoplasts.
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135
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Roessner CA, Warren MJ, Santander PJ, Atshaves BP, Ozaki S, Stolowich NJ, Iida K, Scott AI. Expression of 9 Salmonella typhimurium enzymes for cobinamide synthesis. Identification of the 11-methyl and 20-methyl transferases of corrin biosynthesis. FEBS Lett 1992; 301:73-8. [PMID: 1451790 DOI: 10.1016/0014-5793(92)80213-z] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Nine of the cbi genes from the 17.5 kb cob operon of Salmonella typhimurium previously shown by genetic studies to be involved in the biosynthesis of cobinamide from precorrin-2, have been subcloned and expressed in Escherichia coli. Seven of the gene products were found in the soluble fraction of cell lysates and have been purified. The gene products corresponding to cbi E, F, H and L were shown by SAM binding and by homology with other SAM-binding proteins to be candidates for the methyltransferases of vitamin B12 biosynthesis. The enzymatic functions of the gene products of cbiL and cbiF are associated with C-methylation at C-20 of precorrin-2 and C-11 of precorrin-3.
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Scott AI, Freeman CP. Edinburgh primary care depression study: treatment outcome, patient satisfaction, and cost after 16 weeks. BMJ (CLINICAL RESEARCH ED.) 1992; 304:883-7. [PMID: 1392754 PMCID: PMC1882822 DOI: 10.1136/bmj.304.6831.883] [Citation(s) in RCA: 135] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
OBJECTIVE To compare the clinical efficacy, patient satisfaction, and cost of three specialist treatments for depressive illness with routine care by general practitioners in primary care. DESIGN Prospective, randomised allocation to amitriptyline prescribed by a psychiatrist, cognitive behaviour therapy from a clinical psychologist, counselling and case work by a social worker, or routine care by a general practitioner. SUBJECTS AND SETTING 121 patients aged between 18 and 65 years suffering depressive illness (without psychotic features) meeting the criteria of the Diagnostic and Statistical Manual of Mental Disorders, Third Edition for major depressive episode in 14 primary care practices in southern Edinburgh. MAIN OUTCOME MEASURES Standard observer rating of depression at outset and after four and 16 weeks. Numbers of patients recovered at four and 16 weeks. Total length and cost of therapist contact. Structured evaluation of treatment by patients at 16 weeks. RESULTS Marked improvement in depressive symptoms occurred in all treatment groups over 16 weeks. Any clinical advantages of specialist treatments over routine general practitioner care were small, but specialist treatment involved at least four times as much therapist contact and cost at least twice as much as routine general practitioner care. Psychological treatments, especially social work counselling, were most positively evaluated by patients. CONCLUSIONS The additional costs associated with specialist treatments of new episodes of mild to moderate depressive illness presenting in primary care were not commensurate with their clinical superiority over routine general practitioner care. A proper cost-benefit analysis requires information about the ability of specialist treatment to prevent future episodes of depression.
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137
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Scott AI, Gow SM, Garden W, Shering PA, Whalley LJ. Repeated ECT and prolactin release in depressed patients. Biol Psychiatry 1992; 31:613-6. [PMID: 1581441 DOI: 10.1016/0006-3223(92)90248-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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138
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Scott AI, Rodger CR, Stocks RH, Shering AP. Is old-fashioned electroconvulsive therapy more efficacious? A randomised comparative study of bilateral brief-pulse and bilateral sine-wave treatments. Br J Psychiatry 1992; 160:360-4. [PMID: 1562862 DOI: 10.1192/bjp.160.3.360] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
In-patients suffering from major depressive disorder (endogenous subtype) were randomly allocated to treatment by either traditional ECT with constant-voltage modified sine-wave stimuli (n = 17) or modern, constant-current brief-pulse ECT (n = 14). All treatments were bilateral and monitored by simultaneous recording by EEG. The severity of depressive illness was assessed the day before treatment, after three treatments, and seven days after the last treatment. The improvement and final depression rating scores, the likelihood of recovery, and the average number of treatments received were virtually identical in the two groups. We concluded that the policy of bilateral suprathreshold modern ECT monitored by EEG is as efficacious as traditional ECT.
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139
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Warren MJ, Roessner CA, Ozaki S, Stolowich NJ, Santander PJ, Scott AI. Enzymatic synthesis and structure of precorrin-3, a trimethyldipyrrocorphin intermediate in vitamin B12 biosynthesis. Biochemistry 1992; 31:603-9. [PMID: 1731915 DOI: 10.1021/bi00117a043] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The trimethylated intermediate of vitamin B12 (corrin) biosynthesis, precorrin-3, was produced from various 13C-enriched isotopomers of 5-aminolevulinic acid (ALA), using a multiple-enzyme system containing ALA dehydratase, porphobilinogen deaminase, uro'gen III synthetase, and the S-adenosyl-L-methionine-(SAM)-dependent uro'gen III methyltransferase (M-1) and precorrin-2 methyltransferase (M-2) in the presence of [13C]SAM. Structural analysis of the resulting product, precorrin-3, reveals a close similarity to precorrin-2 but with several subtle differences in the conjugated array of C = C and C = N bonds which reflect the presence of the new C-methyl group at C20 and its influence on the electronic distribution in the dipyrrocorphin chromophore. The implications of this structure for corrin biosynthesis are discussed.
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140
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Narasimhan TR, Safe S, Williams HJ, Scott AI. Effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin on 17 beta-estradiol-induced glucose metabolism in MCF-7 human breast cancer cells: 13C nuclear magnetic resonance spectroscopy studies. Mol Pharmacol 1991; 40:1029-35. [PMID: 1758438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The effects of 17 beta-estradiol, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), and their combination on the metabolism of [1-13C] glucose were determined in cell suspensions of wild-type MCF-7 human breast cancer cells, by 13C NMR spectroscopy. Preliminary studies showed that, during the 7-hr duration of the NMR experiment, the cells maintained their viability and their aryl hydrocarbon responsiveness. Lactate was the major glucose metabolite detected in these studies, and the rate of lactate formation in the untreated (control) and 17 beta-estradiol (10(-9) M)-treated cells was 60 and 86 fmol/cell/hr, respectively; this represented a 40% increase in lactate formation in the cells treated with 17 beta-estradiol; comparable results were observed for the percentage of glucose converted into lactate. In contrast, TCDD (10(-9) M) did not significantly alter the rate of glucose metabolism or lactate formation. Co-treatment of the cells with 17 beta-estradiol (10(-9) M) plus TCDD (10(-8) to 10(-10) M) showed that TCDD completely inhibited the 17 beta-estradiol-induced metabolism of [13C] glucose to lactate in MCF-7 cells. In contrast, 2,8-dichlorodibenzo-p-dioxin (10(-8) M), a weak aryl hydrocarbon receptor agonist, did not inhibit estrogen-induced glucose-to-lactate metabolism in MCF-7 cells. In addition, it was shown that TCDD caused a significant decrease in 17 beta-estradiol-induced lactate formation within 1 hr after treatment, whereas the induction of monooxygenase activity was not observed until 3 hr after exposure of the cells to TCDD. These data indicate that TCDD-induced 17 beta-estradiol metabolism is not related to the decrease in the rate of conversion of glucose to lactate. These results further define the antiestrogenic responses elicited by TCDD and show that 13C NMR spectroscopy provides a unique method for measuring, in real time, the effects of TCDD on specific metabolic pathways.
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141
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Scott AI, Weeks DJ, McDonald CF. Continuation electroconvulsive therapy: preliminary guidelines and an illustrative case report. Br J Psychiatry 1991; 159:867-70. [PMID: 1790461 DOI: 10.1192/bjp.159.6.867] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Despite renewed interest in ECT as a continuation treatment after an episode of depressive illness, few guidelines for its use are available. Meaningful research findings are few, although the potential benefits and risks of modern continuation ECT merit study. We suggest preliminary guidelines and provide an illustrative clinical example.
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Ortiz C, Tellier C, Williams H, Stolowich NJ, Scott AI. Diastereotopic covalent binding of the natural inhibitor leupeptin to trypsin: detection of two interconverting hemiacetals by solution and solid-state NMR spectroscopy. Biochemistry 1991; 30:10026-34. [PMID: 1911768 DOI: 10.1021/bi00105a030] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The naturally occurring peptidyl protease inhibitor leupeptin (N-acetyl-L-leucyl-L-leucyl-L-argininal) has been prepared labeled with 13C at the argininal carbonyl. 13C chemical shift data for the trypsin-leupeptin inhibitor complex in the pH range 3.0-7.6 reveal the presence of two pH-dependent covalent complexes, suggestive of two interconverting diastereomers at the new asymmetric tetrahedral center created by covalent addition of Ser195 to either side of the 13C-enriched aldehyde of the inhibitor. At pH 7 two signals are observable at delta 98.8 and delta 97.2 (84:16 ratio), while at pH 3.0 the latter signal predominates. In the selective proton 13C-edited NOE spectrum of the major diastereomer at pH 7.4, a strong NOE is observed between the hemiacetal proton of the inhibitor and the C2 proton of His57 of the enzyme, thus defining the stereochemistry of the high pH complex to the S configuration in which the hemiacetal oxygen resides in the oxyanion hole. pH titration studies further indicate that the 13C chemical shift of the S diastereomer follows a titration curve with a pKa of 4.69, the magnitude of which is consistent with direct titration of the hemiacetal oxygen. Similar pH-dependent chemical shifts were obtained by using CPMAS 13C NMR, providing evidence for the existence of the same diastereomeric equilibrium in the solid state.
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143
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144
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Oh-hama T, Santander PJ, Stolowich NJ, Scott AI. Bacteriochlorophyll c formation via the C5 pathway of 5-aminolevulinic acid synthesis in Chloroflexus aurantiacus. FEBS Lett 1991; 281:173-6. [PMID: 2015889 DOI: 10.1016/0014-5793(91)80386-h] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Biosynthesis of 5-aminolevulinic acid (ALA) in Chloroflexus aurantiacus, a thermophilic bacterium forming bacteriochlorophyll c, is shown to proceed via the C5 pathway by demonstrating (1) the specific labeling of its chlorin ring with [1 - 13C]glutamate and (2) the enzyme activity to produce ALA from glutamate in a cell-free extract. From the phylogenetic distribution it is suggested that ALA synthetase distributed in some aerobic eubacteria could be monophyletic in origin.
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145
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Higaki T, Tanase S, Nagashima F, Morino Y, Scott AI, Williams HJ, Stolowich NJ. Porcine cytosolic aspartate aminotransferase reconstituted with [4'-13C]pyridoxal phosphate. pH- and ligand-induced changes of the coenzyme observed by 13C NMR spectroscopy. Biochemistry 1991; 30:2519-26. [PMID: 2001379 DOI: 10.1021/bi00223a032] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Apoenzyme samples of aspartate aminotransferase (AspAT) purified from the cytosolic fraction of pig heart were reconstituted with [4'-13C]pyridoxal 5'-phosphate (pyridoxal-P). The 13C NMR spectra of AspAT samples thus generated established the chemical shift of 165.3 ppm for C4' of the coenzyme bound as an internal aldimine with lysine 258 of the enzyme at pH 5. In the absence of ligands the chemical shift of C4' was shown to be pH dependent, shifting 5 ppm upfield to a constant value of 160.2 ppm above pH 8, the resulting pKa of 6.3 in agreement with spectrophotometric titrations. The addition of the competitive inhibitor succinate to the internal aldimine raises the pKa of the imine to 7.8, consistent with the theory of charge neutralization in the active site. In the presence of saturating concentrations of 2-methylaspartic acid the C4' signal of the coenzyme was shown to be invariant with pH and located at 162.7 ppm, midway between the observed chemical shifts of the protonated and unprotonated forms of the internal aldimine. The intermediate chemical shift of the external aldimine complex is thought to reflect the observation of an equilibrium mixture composed of roughly equal populations of the protonated ketoenamine and a dipolar anion species, corresponding to their respective spectral bands at 430 and 360-370 nm. Conversion to the pyridoxamine form was accomplished via reaction of the internal aldimine with L-cysteinesulfinate or by reduction with sodium borohydride, and the resulting C4' chemical shifts were identified by difference spectroscopy. Finally, the line widths of the C4' resonance under the various conditions were measured and qualitatively compared. The results are discussed in terms of the current mechanism and molecular models of the active site of AspAT.
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146
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Stocks R, Scott AI. What happens to patients who frequently harm themselves? A retrospective one-year outcome study. Br J Psychiatry 1991; 158:375-8. [PMID: 2036537 DOI: 10.1192/bjp.158.3.375] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Between 1982 and 1987, 42 patients were selected who had been admitted three times in one week to the Regional Poisoning Treatment Centre in Edinburgh for the treatment of deliberate self-harm. Most (87%) of these admissions related to drug overdose. Most of the patients were young, unemployed, lacking a partner and from the low social classes. Three-quarters of the sample had at least one known conviction and more than a third were known to have served a prison sentence. There was only one patient in whom mental illness was thought to be relevant to the episode of self-harm, although five patients were mildly mentally handicapped. Case notes were reviewed to assess the outcome one year after the index admission. None of the patients had committed suicide, although 36 repeated self-harm during the follow-up year.
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147
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Scott AI, Perini AF, Shering PA, Whalley LJ. In-patient major depression: is rolipram as effective as amitriptyline? Eur J Clin Pharmacol 1991; 40:127-9. [PMID: 2065693 DOI: 10.1007/bf00280065] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The antidepressant efficacy and adverse-effects of rolipram (a dialkoxyphenyl-2-pyrrolidone) were compared to those of amitriptyline in the treatment of depressive illness requiring hospital admission in a double-blind study. Fifty patients meeting DSM-III criteria for Major Depression whose scores on the Hamilton Rating Scale for Depression (HRSD) remained above 17 after 5 to 7 days on placebo were randomly allocated to either treatment. The rate of recovery in those patients treated by amitriptyline was substantially greater than in those patients treated by rolipram. Twice as many patients dropped out of treatment by rolipram because of lack of efficacy or adverse-effects compared with patients treated by amitriptyline. Rolipram produced fewer adverse-effects attributable to cholinergic blockade, but more nausea. We conclude that amitriptyline is more effective than rolipram in the treatment of depressed hospital in-patients.
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148
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Scott AI, Shering PA, Legros JJ, Whalley LJ. Improvement in depressive illness is not associated with altered release of neurophysins over a course of ECT. Psychiatry Res 1991; 36:65-73. [PMID: 2017524 DOI: 10.1016/0165-1781(91)90118-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The hypothesis that the release of vasopressin-associated neurophysin (hNpI) or oxytocin-associated neurophysin (hNpII) is modified by a course of electroconvulsive therapy (ECT) was tested by the measurement of serum neurophysins before and after the first and last ECTs given to 17 unipolar depressed patients. Neither basal nor ECT-induced neurophysin release changed between the first and last ECTs. Data from the present study were combined with data from a previous published study to provide a sample of 29 unipolar depressed patients. In this extended sample, the release of hNpII after the first ECT was significantly correlated with improvement in symptoms of depression over a course of ECT as measured by the Hamilton Rating Scale for Depression and the Montgomery-Asberg Depression Rating Scale.
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149
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Aplin RT, Baldwin JE, Pichon C, Roessner CA, Ian Scott A, Schofield CJ, Stolowich NJ, Warren MJ. Observation of enzyme bound intermediates in the biosynthesis of preuroporphyrinogen by PBG deaminase. Bioorg Med Chem Lett 1991. [DOI: 10.1016/s0960-894x(01)80453-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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150
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Oh-hama T, Stolowich NJ, Scott AI. Characterization of the process of 5-aminolevulinic acid formation from glutamate via the C5 pathway in Clostridium thermoaceticum. THE INTERNATIONAL JOURNAL OF BIOCHEMISTRY 1991; 23:1417-20. [PMID: 1761150 DOI: 10.1016/0020-711x(91)90284-t] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
1. In vitro formation of 5-aminolevulinic acid (ALA) from glutamate required two enzyme fractions, separable on Blue Sepharose affinity chromatography, and a tRNA fraction, which can be replaced by Escherichia coli tRNA(Glu) in the reconstituted assay. 2. Gabaculine was shown to inhibit ALA formation in the complete assay as well as in a defined system consisting of only glutamate-1-semialdehyde and the enzyme fraction not retained on Blue Sepharose. 3. The results indicate that the enzyme system supporting ALA formation in Clostridium thermoaceticum is very similar to the tRNA(Glu)-dependent C5 pathway in plant plastids.
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