RESUMEN
beta-D-Galactosidase, isolated from cloned E. coli, was immobilised on cellulose beads via oxidation with sodium periodate, activation by cyanuric chloride, or diazotisation. beta-D-Galactosidase immobilised via azo bonds showed the highest relative activity and thermostability, and was used for synthesis of disaccharide methyl glycosides.
Asunto(s)
Disacáridos/biosíntesis , Enzimas Inmovilizadas , beta-Galactosidasa/metabolismo , Celulosa , Estabilidad de Medicamentos , Escherichia coli/enzimología , Calor , beta-Galactosidasa/aislamiento & purificaciónRESUMEN
Antibacterial, antifungal and antiprotozoal effects of nine mono- and bishydrazones of glycolaldehyde, glyoxal, methoxyacetaldehyde and glutaraldehyde were studied using eight model organisms. It was found that bishydrazones are much more efficient antimicrobial agents than monohydrazones in the case of all model microorganisms.
Asunto(s)
Antiinfecciosos/farmacología , Hidrazonas/farmacología , Animales , Antibacterianos , Bacillus/efectos de los fármacos , Biotransformación , Candida albicans/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Hidrazonas/metabolismo , Micrococcus/efectos de los fármacos , Fenilhidrazinas/biosíntesis , Fenilhidrazinas/metabolismo , Pseudomonas aeruginosa/efectos de los fármacos , Saccharomyces cerevisiae/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Trichomonas vaginalis/efectos de los fármacosRESUMEN
The antimicrobial effect of 14 sugar osazones and anhydro sugars was studied with model strains of Micrococcus luteus, Bacillus licheniformis, Escherichia coli and strains Staphylococcus aureus and Pseudomonas aeruginosa isolated from clinical material. The relationship between the structure of these compounds, their solubility in water and 1-octanol and antimicrobial effect was investigated.
Asunto(s)
Bacterias/efectos de los fármacos , Hexosas/farmacología , Bacillus/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Hidrazonas/farmacología , Micrococcus/efectos de los fármacos , Pseudomonas aeruginosa/efectos de los fármacos , Solubilidad , Staphylococcus aureus/efectos de los fármacos , Relación Estructura-ActividadRESUMEN
Aerobic fermentation of media or solutions containing 2-deoxy-D-lyxo-hexose and calcium carbonate by bacterial cells capable of oxidizing aldoses to aldonic acids was used to prepare 2-deoxy-D-lyxo-hexonic acid; the acid was isolated in a 62% yield in the form of its 1,4-lactone.
Asunto(s)
Desoxiazúcares/metabolismo , Pseudomonas aeruginosa/metabolismo , Aspergillus niger/metabolismo , Fermentación , Azúcares Ácidos/metabolismoRESUMEN
The biosynthesis of starch was investigated in the reaction catalyzed by plant alpha(1 leads to 4)-glucan phosphorylase using alpha-D-glucopyranosyl phosphate and its deoxy analogues as substrates. It was found that the hydroxyl groups at the positions C-2, C-3, C-4 and C-6 in the glucose moiety of the molecule of alpha-D-glucopyranosyl phosphate are not essential for its substrate properties in the transglycosylic reaction. The affinity of plant (alpha(1 leads to 4)-glucan phosphorylase and the rate of hexose incorporation into alpha(1 leads to 4)-glucan decreases in the following sequence: alpha-D-glucopyranosyl phos-phosphate, 2-deoxy-, 6-deoxy, 4-deoxy, and 3-deoxy-alpha-D-glucopyranosyl phosphate. The deoxyglucosyl analogues of alpha-D-glucosylpyranosyl phosphate act as competitive inhibitors on the elongation reaction of the alpha(1 leads to 4) chains of starch. It was found that more than one residue of 2-deoxy-D-glucose or 6-deoxy-D-glucose can be incorporated into the nonreducing terminus of alpha(1 leads to 4)-glucan chains of starch.
Asunto(s)
Desoxiazúcares , Desoxiglucosa , Almidón/análogos & derivados , Cinética , Plantas/enzimología , Almidón/biosíntesis , alfa-Amilasas/metabolismoRESUMEN
The biosynthesis of alpha,alpha'-trehalose was investigated in a reaction catalyzed with yeast UDP-Glc :glucose-6-phosphate 1-glucosyl transferase. It was revealed that the hydroxyls at positions C-2, C-3, C-4 and C-6 are not essential for preserving its substrate properties in this reaction. The affinity of the enzyme and the rate of hexose incorporation into trehalose decreases in following sequence: UDP-glucose, UDP-2-deoxy-D-glucose, UDP-6-deoxy-d-glucose, UDP-4-deoxy-D-glucose and UDP-3-deoxy-D-glucose.
Asunto(s)
Desoxiazúcares/biosíntesis , Disacáridos/análogos & derivados , Trehalosa/análogos & derivados , Glucosiltransferasas/metabolismo , Cinética , Saccharomyces cerevisiae/enzimología , Relación Estructura-ActividadRESUMEN
The paper describes chemical synthesis of uridine diphosphate 2-deocyglucose (UDPdGLc) through reaction of uridine 5'-phosphomorpholidate with 2-deoxy-a-D-glucopyranosyl phosphate. The prepared analog of uridine diphosphate glucose (UDPGlc) served as a substrate for calf liver UDPGlc dehydrogenases (EC 1.1.1.22), the reaction product was identified as nucleotide deoxyhexuronic acid derivative. The apparent Km for UDPdGlc was found to be 60 times that of UDPGlc, and the relative V value for the analog was 0.09. The peculiar lag-eriod in reaction kinetics has been observed for the analog and is presumably connected with the slow rate of the initial stages of the reaction. UDPdGlc was found to be quite an efficient substrate for UDPGlc 4-epimerases (EC 5.13.2) from yeast, calf liver and mung bean seedlings.
Asunto(s)
Desoxiazúcares , Desoxiglucosa , Azúcares de Uridina Difosfato , Oxidorreductasas de Alcohol/metabolismo , Animales , Carbohidrato Epimerasas/metabolismo , Bovinos , Desoxiglucosa/análogos & derivados , Cinética , Hígado/enzimología , Oxidación-Reducción , Plantas/enzimología , Saccharomyces cerevisiae/enzimología , Estereoisomerismo , Relación Estructura-Actividad , Nucleótidos de Uracilo/metabolismo , Azúcares de Uridina Difosfato/síntesis químicaRESUMEN
Fermentation of a medium containing 5% 2-deoxy-D-glucose and barium carbonate by a strain of Pseudomonas aeruginosa yielded barium 2-deoxy-D-gluconate. The yield was 77% theoretical. The strain in question makes it possible to prepare directly calcium, magnesium, manganese and ferrous salts of 2-deoxy-D-gluconic acid. A treatment of 5% solution of 2-deoxy-D-glucose with commercial glucose oxidase preparation caused also a complete dehydrogenation.