RESUMEN
The strains of yeast-like fungi isolated from HIV-infected people in 1994-2005 were examined. It was found that a share of non-albicans strains increased up to 46.2%, in monoculture they were present in 40% of examined patients, Candida glabrata (21.3%) being the dominant species. The definition of proteolytic activity as one of the factors of pathogenicity showed that it was typical of 90% of museum strains and 58% of fresh isolates.
Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/microbiología , Mucosa Bucal/microbiología , Micosis/microbiología , Levaduras/aislamiento & purificación , Humanos , Virulencia , Levaduras/clasificación , Levaduras/patogenicidadRESUMEN
Sensitivity of museum and fresh strains to antimycotics has been determined. 5-Fluorocytosine (86.2%) and amphotericine B (93.2%) were highly effective as to results on test-systems, considerable part of strains was resistant to fluconasole (93.2%) and itraconasole (62.1%). Due to disk-diffusion method it was determined that nystatine was an effective inhibitor of growth of 100% of all species cultures, amphotericine B--93.3%, resistance to clotrimasole was 56.6%. During the last three years the part of polyresistant strains of yeastlike fungi exceeds considerably the critical level. A comparison of antibiotic sensitivity of C. albicans representatives and strains of non-albicans species did not manifest cardinal differences.
Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/microbiología , Antifúngicos/farmacología , Infecciones por VIH/microbiología , Micosis/microbiología , Levaduras/efectos de los fármacos , Levaduras/aislamiento & purificación , Farmacorresistencia Fúngica , Humanos , Pruebas de Sensibilidad MicrobianaRESUMEN
The use of commercial test-systems has not allowed to identify 11 atypical clinical strains of nonfermenting Gram-negative bacteria. The divergences arised not only under their species identification, but also under generic one. On the basis of studying the fatty acid composition of the cell wall all isolates were referred to Pseudomonas genus. The further control of species belonging of the strains carried out with the use of 45 tests and the computer program www.imv.kiev.ua/PsmIK/default.htm has confirmed, that five isolates are representatives of P. aeruginosa, two ones were identified as P. fluorescens, and three more as Pseudomonas spp.
Asunto(s)
Ácidos Grasos/química , Pseudomonas , Cromatografía de Gases , Clasificación , Pseudomonas/química , Pseudomonas/clasificación , Pseudomonas/aislamiento & purificaciónRESUMEN
The vital ability, serological properties, antibioticograms and biochemical properties of collection strains and new isolates of Shigella sonnei have been studied. It was ascertained that the determined factors are sufficiently variable, thus they cannot be used as the independent basis for the classification of pathogens.
Asunto(s)
Shigella sonnei/clasificación , Shigella sonnei/aislamiento & purificación , Serotipificación , Shigella sonnei/genética , UcraniaRESUMEN
The viability, purity, biological and serological properties of museum strains of Shigella flexneri which were kept in lyophilized state during above 30 years were studied. Primary serological characteristics were specified, it was established that type 2a is the predominant serotype independent of the years and regions of isolation. Some strains lost antigens as a result of the long-term preservation or reinoculation on agar media.
Asunto(s)
Preservación Biológica/métodos , Shigella flexneri/clasificación , Shigella flexneri/crecimiento & desarrollo , Liofilización , Serotipificación , Shigella flexneri/genética , Shigella flexneri/aislamiento & purificación , Factores de TiempoRESUMEN
Among the collection strains of S. flexneri 10.5; 5.5; 2.6; 2.6 and 7.9% of strains were resistant to ampicillin, tetracycline, ceftryaxon, cefasoline, chloramphenycol, respectively. The maximum number of R-determinants of one strain was 4. The strains resistant to cefalosporynes were not revealed; among newly isolated strains of this agent, these strains resistant to ampicilline, tetracycline and chloramphenycol made 20%. Among the collection and newly isolated strains of S. flexneri, isolated 50 and more years ago, the part of colicinogenic ones was 10%. And, on the contrary both for the collection and newly isolated strains of S. sonnei colicinogenic activity is specific biological property (above 80%). Correlation relation between two tested pathogenic factors, certain serovars and biovars of the agents, was not revealed.
Asunto(s)
Antibacterianos/farmacología , Colicinas/biosíntesis , Farmacorresistencia Bacteriana/efectos de los fármacos , Shigella flexneri/efectos de los fármacos , Shigella sonnei/efectos de los fármacos , Escherichia coli K12/metabolismo , Shigella flexneri/aislamiento & purificación , Shigella flexneri/metabolismo , Shigella sonnei/aislamiento & purificación , Shigella sonnei/metabolismoRESUMEN
Aspartokinases have been isolated from the cell-free extracts of Plectonema boryanum, Anabaena variabilis and Synechococcus cedrorum. Their physico-chemical characteristics and peculiarities of retroregulation by amino acids were studied. It has been shown that in P. boryanum cells aspartokinase reaction is catalyzed by only one enzyme, which is similar to the previously described bacterial origin enzymes. Three izoenzymes, which differ in their main properties and amino acids-effectors, have been founded in the cells of A. variabilis. One enzyme with aspartokinase activity, which differs from other cyanobacteria enzymes in some physico-chemical features has been founded in the cells of S. cedrorum.
Asunto(s)
Aspartato Quinasa/química , Cianobacterias/enzimología , Aspartato Quinasa/metabolismo , Isoenzimas/química , Isoenzimas/metabolismo , Especificidad de la EspecieRESUMEN
The associative cultures of cyanobacteria were selected which may be used for development of technology of tertiary treatment of sewage for yeast and alcohol production plants. Growth parameters of associations were studied during periodic and continuous cultivation. When studying the influence of flowing speed for some exponents of treatment it was shown that cultivation of cyanobacteria should be carried out with the change of volume not more than 0.01 h. Final treatment 0.010 h-1 in order to return sewage to natural water reservoirs may be carried out by means of Oscillatoria sp. in bioponds.
Asunto(s)
Cianobacterias/crecimiento & desarrollo , Etanol , Residuos Industriales , Aguas del Alcantarillado/microbiología , Purificación del Agua/métodos , Levaduras , Industria de Alimentos , Contaminación del Agua/prevención & controlRESUMEN
The species variety of yeasts of the genus Candida in children and patients with AIDS has been investigated. Composition of the studied species was found to be similar in newborns and in women with candidiasis. In order to create new probiotics with antifungal properties, the cluster analysis of antagonistic activity of some Bacillus strains against Enterobacteriaceae, Candida, normoflora and food-fermenting lactobacteria has been conducted. There were selected the combinations of some Bacillus strains, which effectively inhibited pathogenic and opportunistic microorganisms and at the same time had no effect on intestinal normoflora.
Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/tratamiento farmacológico , Infecciones Oportunistas Relacionadas con el SIDA/microbiología , Antifúngicos/uso terapéutico , Bacillus , Candida/aislamiento & purificación , Candidiasis/tratamiento farmacológico , Candidiasis/microbiología , VIH-1 , Probióticos/uso terapéutico , Adulto , Antibiosis , Candida/clasificación , Niño , Enterobacteriaceae , Femenino , Humanos , Recién Nacido , Lactobacillus , StreptococcusRESUMEN
The influence of cyanophage A-1 reproduction on glutamate dehydrogenase (GDG) and glutamine synthetase (GS) in A. variabilis cells was studied. It was determined that the both enzymes are intensified by 70% and 30%, accordingly. Isoenzymes of GDG and GS were isolated from native and infected cells of cyanobacteria, they had various physicochemical properties. It is concluded that cyanophage development causes the specific modification of cell enzymes.
Asunto(s)
Aminoácidos/biosíntesis , Anabaena/metabolismo , Bacteriófagos/crecimiento & desarrollo , Glutamato Deshidrogenasa/metabolismo , Glutamato-Amoníaco Ligasa/metabolismo , Isoenzimas/metabolismo , Anabaena/virología , Fenómenos Químicos , Química FísicaRESUMEN
The promoting effect of electromagnetic field (EMF) on biosynthesis and activity of extracellular proteinase and lectin in B. subtilis 316 M was observed. It caused 1.5- and 4-fold increase of the metabolites yield respectively. The EMF stimulated a 2-fold activation of lectin, rise of the enzyme activity and a shift of it pI from 11.4-11.5 to 9.2-9.3.
Asunto(s)
Bacillus subtilis/efectos de la radiación , Campos Electromagnéticos , Lectinas/efectos de la radiación , Serina Endopeptidasas/efectos de la radiación , Bacillus subtilis/metabolismo , Estabilidad de Enzimas , Focalización Isoeléctrica , Lectinas/aislamiento & purificación , Serina Endopeptidasas/aislamiento & purificaciónRESUMEN
The effect of cyanophage LPP-3 reproduction on glutamate dehydrogenase and glutamine synthetase (GS) in P boryanum cells have been studied. It was determined that the both reactions are intensified by 135% and 220%, accordingly. Isoenzymes of GS were purified from native and infected cell of cyanobacteria. Their physical-and-chemical properties are different. The cyanophage development probably causes specific modification of the cell enzymes.
Asunto(s)
Bacteriófagos/fisiología , Cianobacterias/enzimología , Glutamato Deshidrogenasa/metabolismo , Glutamato-Amoníaco Ligasa/metabolismo , Isoenzimas/metabolismo , Replicación Viral , Cianobacterias/virología , Glutamato-Amoníaco Ligasa/aislamiento & purificación , Isoenzimas/aislamiento & purificación , NAD/metabolismo , NADP/metabolismoRESUMEN
It has been studied how reproduction of LPP-3 in Plectonema boryanum cells influences the alanine dehydrogenase activity. It has been found that immediately after the virus adsorption the enzyme activity falls by 50% and the anabolic reaction is blocked. Physicochemical properties of the enzyme vary as well. An infected cell has one isoenzyme-octamer with pl 9.1-9.2, pH-optimum by action 9-10, molecular weight about 27 kDa.
Asunto(s)
Aminoácido Oxidorreductasas/metabolismo , Bacteriófagos/genética , Cianobacterias/enzimología , Isoenzimas/metabolismo , Alanina-Deshidrogenasa , Fraccionamiento Químico , Fenómenos Químicos , Química Física , Concentración de Iones de Hidrógeno , Peso MolecularRESUMEN
Alanine dehydrogenase activity of Plectonema boryanum cells was studied. It was found, that only NAD(H) may be used as the coenzyme. Kinetical parameters for substrates and coenzymes were determined. 2 pH-optima of action have been established for biosynthetic and anabolic reactions. Two isoenzymes of ADG were cleaned using the methods of ion-exchange chromatography and isoelectric focusing. Some physical-chemical properties were studied: pHopt--9-10 and 4.0; temperature optimum -40 degrees C; pI--8.2 and 6.4; molecular weight--50.65 and 52.48 kDa for ADG-1 and ADG-2, respectively. Both enzymes have the subunit structure. Every enzyme is composed by 4 identical polypeptides.
Asunto(s)
Alanina/química , Aminoácido Oxidorreductasas/análisis , Cianobacterias/enzimología , NAD/química , Piruvatos/química , Alanina-Deshidrogenasa , Catálisis , Fenómenos Químicos , Química Física , Concentración de Iones de Hidrógeno , Isoenzimas/análisis , Cinética , Peso Molecular , Ácido Pirúvico , Especificidad por Sustrato , TemperaturaRESUMEN
The effect of development of cyanophage infection on the activity of aspartate kinase of Plectonema boryanum has been studied. It has been determined that activity of aspartate kinase increased during early period of reproduction of cyanophage. It coincided in time with the increase of the level of amino acids of aspartate family. Isoenzymes of aspartate kinase were isolated from the infected cells purified and studied. Expression of viral genome is accompanied with the appearance of four new isoenzymes determined by virus. The revealed aspartate kinases are not subject of regulation by amino acids (the end-products of biosynthesis) according to the principle of feed-back inhibition.
Asunto(s)
Aspartato Quinasa/metabolismo , Bacteriófagos/crecimiento & desarrollo , Cianobacterias/enzimología , Isoenzimas/metabolismo , Adsorción , Aminoácidos/metabolismo , Bacteriófagos/genética , Cianobacterias/virología , Retroalimentación , Genoma Viral , Isoenzimas/aislamiento & purificaciónRESUMEN
Aspartate kinase activity in cells of A. variabilis has been studied in the dynamics of development of virus infection. An early period of reproduction of cyanophage A-1 has been determined to be conjugated with the increase of biosynthesis of amino acids from aspartate family. Five isoenzymes of aspartate kinase were isolated and purified from A. variabilis cells during early development period of cyanophage A-1. Physicochemical properties and influence of amino acids of aspartate family on the activity of homogeneous isoenzymes have been studied. Retroinhibition effect was not observed in infected cyanobacteria cells, which probably enables one to increase 2-7 times the concentration of amino acids in a cell. Such an increase of the amino acids pool is apparently necessary for realization of viral genome strategy.
Asunto(s)
Aspartato Quinasa/fisiología , Bacteriófagos/fisiología , Cianobacterias/virología , Isoenzimas/fisiología , Replicación Viral/fisiología , Aspartato Quinasa/química , Fenómenos Químicos , Química Física , Isoenzimas/químicaRESUMEN
Aspartate-kinase (ASK) activity of filamentous cyanobacteria A. variabilis and its dependence on physico-chemical factors and substrate concentration in the reaction mixture have been studied. Three isoenzymes ASK-1, ASK-2 and ASK-3 which differ in the values of pH-optima, molecular weight, isoelectric points and effector of retro-inhibition have been isolated by ion-exchange chromatography. High level of inhibition of summary ASK of the cell-free extract can be reached only in a case of simultaneous addition of all amino acids, the final products of this biosynthetic pathway into the incubation mixture.
Asunto(s)
Aspartato Quinasa/metabolismo , Cianobacterias/enzimología , Isoenzimas/metabolismo , Aspartato Quinasa/química , Aspartato Quinasa/aislamiento & purificación , Catálisis , Fenómenos Químicos , Química Física , Concentración de Iones de Hidrógeno , Punto Isoeléctrico , Isoenzimas/química , Isoenzimas/aislamiento & purificación , Peso MolecularRESUMEN
The influence of electromagnetic field on the subtilisin of Bacillus subtilis strain 316 M preparation has been studied. It is the increase 30-60% of the proteolytic activity during 60-100 min treatment was observed. The effect of activation is stable for a month at +4 degrees C. The increase of the proteolytic activity is connected with conformational changes of the enzyme molecule, with the decrease of pI from 11.4 to 9.2 in particular.
Asunto(s)
Bacillus subtilis/enzimología , Campos Electromagnéticos , Subtilisinas/efectos de la radiación , Fenómenos Químicos , Química Física , Activación Enzimática/efectos de la radiación , Estabilidad de Enzimas/efectos de la radiación , Conformación Proteica , Subtilisinas/químicaRESUMEN
The enzymic activity of aspartate kinase from filamentous cyanobacteria Plectonema boryanum at the logarithmic phase of growth has been studied. Aspartate kinase was purified eleven times and extracted in functionally homogeneous state from the cell-free extract by the methods of ammonium sulphate salting-out, ion-exchange chromatography and isoelectric focusing. Some physical and chemical characteristics of the enzyme have been studied: pI-7.2; optimum pH-9.0; optimum temperature-55 degrees C. The dependence of enzymatic reaction on concentration of substrates, co-enzymes, cofactors and protein has been established. Regulation of aspartate kinase activity by amino acids of the aspartate family has been investigated. L-threonine, L-homoserine and L-isoleucine (0.01-0.001 M) have a pronounced inhibitory effect. L-lysine and L-methionine are not immediate inhibitors of aspartate kinase but intensify the inhibitory effect of threonine by the cumulative mechanism.
Asunto(s)
Aspartato Quinasa/aislamiento & purificación , Cianobacterias/enzimología , Aminoácidos/metabolismo , Aspartato Quinasa/química , Aspartato Quinasa/metabolismo , Catálisis , Fenómenos Químicos , Química Física , Cianobacterias/crecimiento & desarrolloRESUMEN
The dynamics of the consumption of major carbon and nitrogen sources and the biosynthesis of hydrolytic enzymes were studied in Bacillus mesentericus grown on semisynthetic media. Conditions were chosen that provide the obtaining of the culture liquid with predominantly proteolytic or amylolytic activity. The replacement of maltose with native starch resulted in more intensive accumulation of the biomass and hydrolytic enzymes, and in more rapid (by 3-5 hr) transformation from the logarithmic to the stationary growth phase.