751
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Kennedy JF, Kay IM. The use of titanium (IV) oxide for the immobilisation of carbohydrate-directed enzymes. Carbohydr Res 1977; 56:211-8. [PMID: 20228 DOI: 10.1016/s0008-6215(00)83343-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The use of particles of porous titanium (IV) oxide as a suitable matrix for enzyme immobilisation has been investigated with dextranase. Treatment of the particles with enzyme in the presence and absence of ammonium ions showed that the presence of ammonia induced a greater coupling of protein, whereas a greater retention of enzyme specific activity was achieved in the absence of ammonia. Properties of the immobilised enzyme include a pH-dependence and reversibility of the coupling between enzyme and matrix. The immobilised dextranase was most stable at pH 5.0. Automated analytical techniques for measuring the activity of dextranase and other polysaccharidases in soluble and insoluble forms are also reported.
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752
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Kennedy JF, Fox JE. The fully automatic ion-exchange and gel-permeation chromatography of neutral monosaccharides and oligosaccharides with a Jeolco JLc-6AH analyser. Carbohydr Res 1977; 54:13-21. [PMID: 861967 DOI: 10.1016/s0008-6215(00)80554-6] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Experiences with a Jeolco JLC-6AH carbohydrate analyser used to provide a fully automated analysis service for neutral mono- and oligo-saccharides have been summarised. Modifications have been made to the equipment to extend its application, and a method for routine separations of oligosaccharides (d.p. 2--15) has been established. The degree of separation achieved is far superior to that which may be obtained by gel-filtration techniques under gravity- or peristaltic-pump-aided flow. The versatility and adaptability of equipment for use with assays other than the standard orcinol-sulphuric acid reaction shows that it is not too inconvenient to interchange between various assays and separations.
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753
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Nakato T, Locher FA, Glover JR, Kennedy JF. Wave Entrainment of Sediment from Rippled Beds. ACTA ACUST UNITED AC 1977. [DOI: 10.1061/jwpcdx.0000020] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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754
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Kennedy JF, Barker SA, Humphreys JD. Zirconium-hydroxide-mediated alkaline hydrolysis of phosphate esters. ACTA ACUST UNITED AC 1977. [DOI: 10.1039/p19770000753] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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755
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Abstract
A novel, water, insoluble, stable coating has been attached to various metals, which is capable of covalent attachment to enzymes. The coating (aminobenzoic acid-formaldehyde resin) can be attached to nickel, cobalt, tin, iron, and aluminium. beta-D-Glucosidase has been attached to the coated metals by diazotisation of the coating. The stability and usefulness of the resulting, metallic enzyme-preparations is discussed with special emphasis on the value of ferromagnetic supports for enzymes.
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756
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757
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Abstract
The free acids, sodium salts, and lactones of several hexuronic acids have been studied as their O-trimethylsilyl derivatives by gas-liquid chromatography using SE-30 and XE-60 liquid phases. Silylation was best performed in methyl sulphoxide. The equilibrium between the various forms of a hexuronic acid in methyl sulphoxide was also studied by g.l.c. following silylation. The hexamethyldisilazane used in the silylation disturbed the equilibrium attained in the solvent, but this was overcome by premixing the hexamethyldisilazane with chlorotrimethylsilane. Methyl sulphoxide and the silylating reagents gave a two-phase system in which the derivative was favourably partitioned into the upper layer. Partition coefficients and stabilities of the derivatives were measured, and a g.l.c. method for the analysis of the hexuronic acids was thereby developed. The oximes of the hexuronic acids were studied as alternative derivatives for g.l.c., and their equilibrium compositions and g.l.c. retention times are recorded.
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758
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Kennedy JF, Barker SA, Humphreys JD. Microbial cells living immobilised on metal hydroxides. Nature 1976; 261:242-4. [PMID: 775343 DOI: 10.1038/261242a0] [Citation(s) in RCA: 104] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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759
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Kennedy JF, Chaplin MF. The structures of the carbohydrate moieties of the alpha subunit of human chorionic gonadotrophin. Biochem J 1976; 155:303-15. [PMID: 938481 PMCID: PMC1172836 DOI: 10.1042/bj1550303] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The alpha subunit of human chorionic gonadotrophin was reduced with dithiothreitol followed by carboxymethylation with iodoacetic acid. The modified glycoprotein was hydrolysed with trypsin to give various peptides, the identities of which were established, and glycopeptides. The glycopeptides were separated by gel filtration and ion-exchange chromatography; they were subjected to component analysis and were found to represent the two carbohydrate moieties in the parent glycoprotein. Sequential removal with glycoside hydrolases of monosaccharide units from the glycopeptides demonstrated (1) that galactose, mannose, glucosamine (2-amino-2-deoxyglucose) and neuraminic acid (5-amino-3,5-dideoxy-glycero-galacto-2-nonulosonic acid) residues possess the D configurations, (2) that the glucosamine units are N-acetylated and (3) the order of the monosaccharide units in the chain, the neuraminic acid units being furthest from the peptide backbone of the subunit and substituting the D-galactose units. Methylation analysis of the glycopeptides by adaptation of the Hakomori technique demonstrated that: (4) D-galactose, D-mannose and N-acetylglucosamine (2-acetamido-2-deoxy-D-glucose) units exist in the pyranose forms; (5) the D-galactopyranose units are linked in the 1 and 6 positions; (6) the D-mannopyranose units exist in several forms, one in a terminal non-reducing position, one as 1,2-linked residues and some as 1,6-linked branch points; (7) the N-acetylglucosamine units are 1,6-linked. On the basis of the results of methylation and enzymic analysis, structures are proposed for the carbohydrate moieties and the assignments are compared with other data previously obtained by periodate-oxidation studies [Kennedy et al. (1974) Carbohydr. Res. 36, 369-377].
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760
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Kennedy JF, Humphreys JD. Active immobilized antibiotics based on metal hydroxides. Antimicrob Agents Chemother 1976; 9:766-70. [PMID: 949174 PMCID: PMC429618 DOI: 10.1128/aac.9.5.766] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The water-insoluble hydroxides of zirconium (IV), titanium (IV), titanium (III), iron (II), vanadium (III), and tin (II) have been used to prepare insoluble derivatives of a cyclic peptide antibiotic by a facile chelation process. Testing of the antibacterial activities of the products against two gram-positive and two gram-negative bacteria showed that in the majority of cases the water-insoluble antibiotics remained active against those bacteria susceptible to the parent antibiotic. The power of the assay system has been extended by the novel use of colored organisms to aid determinations where the growth of normal organisms could not be distinguished from the appearance of the supporting material. Insoluble derivatives of neomycin, polymyxin B, streptomycin, ampicillin, penicillin G, and chloramphenicol were prepared by chelation with zirconium hydroxide, and these derivatives similarly reflected the antibacterial activities of the parent compounds. Several of the metal hydroxides themselves possess antibacterial activity due to complex formation with the bacteria. However, the use of selected metal hydroxides can afford a simple, inexpensive, and inert matrix for antibiotic immobilization, resulting in an antibacterial product that may possess slow-release properties. The mechanisms by which the metal hydroxide-antibiotic association-dissociation may occur are discussed.
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761
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Kennedy JF, Keep PA, Catty D. The separation of rabbit allotypic b4 immunoglobulin from b4-negative immunoglobulin by affinity chromatography on immunoadsorbents prepared from cellulose trans-2,3-carbonate. Biochem Soc Trans 1976; 4:135-7. [PMID: 826417 DOI: 10.1042/bst0040135] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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762
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Kennedy JF, Kay IM. Hydrous titanium oxides--new supports for the simple immobilisation of enzymes. JOURNAL OF THE CHEMICAL SOCIETY. PERKIN TRANSACTIONS 1 1976:329-35. [PMID: 942971 DOI: 10.1039/p19760000329] [Citation(s) in RCA: 40] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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763
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Kennedy JF, Barker SA, Humphreys JD. Insoluble complexes of amino-acids, peptides, and enzymes with metal hydroxides. JOURNAL OF THE CHEMICAL SOCIETY. PERKIN TRANSACTIONS 1 1976:962-7. [PMID: 944717 DOI: 10.1039/p19760000962] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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764
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Kennedy JF. Chemical and biochemical aspects of the glycosaminoglycans and proteoglycans in health and disease. Adv Clin Chem 1976; 18:1-101. [PMID: 130790 DOI: 10.1016/s0065-2423(08)60296-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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765
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Abstract
Titanium compounds affect the measurement of D-glucose oxidase (and therefore D-glucose) by the D-glucose-D-glucose oxidase-peroxidase-2,2'-azinobis-(3-ethylbenzothiazoline-6-sulphonic acid) assay system. The validity of measurement of the activity of D-glucose oxidase immobilised on supports based on titanium oxides is affected by complexation of the intermediate hydrogen peroxide with the support, and such supports may prove to be unsuitable for the immobilisation of D-glucose oxidase. The formation of titanic peroxides is among the reasons discussed for the various interactions encountered. The use of the assay system for the determination of D-glucose oxidase contaminated with catalase and for the determination of hydrogen peroxide is also described.
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766
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Kennedy JF. Letter: Regulation of medical practice by government. N Engl J Med 1975; 293:942. [PMID: 1178002 DOI: 10.1056/nejm197510302931828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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767
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Kennedy JF, Schreiber JR, Andreassen BK. Perfusion of human ovaries in vitro with artificial medium: metabolism and steroidogenesis. Am J Obstet Gynecol 1975; 122:863-71. [PMID: 1146937 DOI: 10.1016/0002-9378(75)90729-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
A study was made of ovaries perfused in vitro with a liquid fluorocarbon that was stabilized in emulsion by a nonionic detergent to which tissue culture medium was added. A pulsatile flow was used in an organ preservation system under aseptic conditions. Glucose was utilized and lactate produced at a fairly constant rate for as long as 20 hours of perfusion. 14-C-progesterone and 14-C-17alphaOH-progesterone were synthesized from 14-C-acetate and estradiol was secreted. The production of these steroids by the perfused ovary appears to be responsive to gonadotropins.
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768
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Abstract
The mercapto groups of cellulose xanthate can reversibly form disulphide bridges with L-cysteine. This property has been utilised for the immobilisation of a protein and an enzyme. These macromolecules, as polythiol derivatives, formed disulphide linkages with the matrix without serious disturbance of their active sites, became firmly bound to the xanthate, and were not eluted by normal washing conditions. Cellulose xanthate is a cheap, easily prepared matrix which permits a simple coupling reaction. The immobilisation process is selectively reversible.
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769
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Migeon BR, Kennedy JF. Evidence for the inactivation of an X chromosome early in the development of the human female. Am J Hum Genet 1975; 27:233-9. [PMID: 1124767 PMCID: PMC1762755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Studies of somatic tissues and cultured cells, including fibroblast clones, from human embryos heterozygous for the electrophoretic variants of glucose-6-phosphate dehydrogenase confirm that one X chromosome is inactivated very early in embryonic development and indicate that X inactivation has occurred in the majority of cells from a variety of tissues at least by 5 weeks from conception.
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770
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Kennedy JF, Barker SA, Zamir A. Active insolubilized antibiotics based on cellulose-metal chelates. Antimicrob Agents Chemother 1974; 6:777-82. [PMID: 4451349 PMCID: PMC444735 DOI: 10.1128/aac.6.6.777] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Cellulose was converted into a more reactive form by chelation with the transition metals titanium(III), iron(III), tin(IV), vanadium(III), and zirconium(IV). The remaining unsubstituted ligands of the transition metal ions were found to be amenable to replacement by electron-donating groups of antibiotic molecules. Ampicillin, gentamicin, kanamycin, neomycin, paromomycin, polymyxin B, and streptomycin were used as antibacterial antibiotics, and amphotericin B and natamycin were used as antifungal antibiotics. Antibacterial activity of the products was tested against two gram-positive and two gram-negative bacteria, and antifungal activity was tested against four fungi. That the antibacterial antibiotics had complexed with the cellulose-metal chelates was demonstrated in that the product cellulose-metal-antibiotic chelates exhibited antibiotic activities whereas the metal chelates of cellulose themselves were inactive. Of 140 tests conducted, cellulose-metal-antibiotic chelates were active in 102 cases. Since the antibiotic derivatives were water insoluble and in fact retain some of the antibacterial activities of the parent compounds, the chelation method provides a facile way of rendering cellulose surfaces, etc., resistant to microbial attack over and above that degree of protection afforded by noncovalent adsorption of the antibiotic to cellulose itself. The underlying principles of the chelation reactions involved are discussed in detail.
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771
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Kennedy JF, Chaplin MF, Stacey M. Periodate oxidation, acid hydrolysis, and structure-activity relationships of human-pituitary, follicle-stimulating hormone and human chorionic gonadotrophin. Carbohydr Res 1974; 36:369-77. [PMID: 4371971 DOI: 10.1016/s0008-6215(00)83058-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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772
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Paily PP, Macagno EO, Kennedy JF. Winter-Regime Thermal Response of Heated Streams. ACTA ACUST UNITED AC 1974. [DOI: 10.1061/jyceaj.0003931] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
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773
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Lowrie DB, Pearce JH, Kennedy JF. The effect of osmotic variation upon the growth of Vibrio fetus. JOURNAL OF GENERAL MICROBIOLOGY 1974; 80:541-8. [PMID: 4596990 DOI: 10.1099/00221287-80-2-541] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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774
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Kennedy JF, Rosevear A. Improvement of the enzyme immobilisation characteristics of macroporous cellulose trans-2,3-carbonate by pre-swelling in dimethyl sulphoxide. ACTA ACUST UNITED AC 1974. [DOI: 10.1039/p19740000757] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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775
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