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1.
Braz. j. microbiol ; 45(4): 1179-1186, Oct.-Dec. 2014. graf, tab
Artigo em Inglês | LILACS | ID: lil-741267

RESUMO

Two mesophilic streptomycetes (S. violaceoruber and S. spiroverticillatus) were selected to study their Poly R-478 decolorization ability and lignocellulose solubilizing activity. Both strains were able to degrade Poly R-478 dye and ferulic acid during growth on a minimal salts medium. The Poly R-478 decolorizing activities of both strains were induced by adding different carbon sources to the culture media. S. violaceoruber could decolorize 63% of Poly R-478 after 24 h. Both strains could solubilize straw and produce acid-precipitable polymeric lignin (APPL) with different efficiency. From the major extracellular enzymes recovery of both strains on rice and wheat straw, we can predicate that the biodegradation process was partial indicating a possible utilization in biological delignification.


Assuntos
Antraquinonas/metabolismo , Lignina/metabolismo , Polímeros/metabolismo , Streptomyces/metabolismo , Biotransformação , Ácidos Cumáricos/metabolismo , Meios de Cultura/química , Oryza/metabolismo , Caules de Planta/metabolismo , Streptomyces/crescimento & desenvolvimento , Triticum/metabolismo
2.
Braz. j. microbiol ; 45(3): 919-928, July-Sept. 2014. graf, tab
Artigo em Inglês | LILACS | ID: lil-727021

RESUMO

The selection of new microorganisms able to produce antimicrobial compounds is hoped for to reduce their production costs and the side effects caused by synthetic drugs. Clavulanic acid is a β-lactam antibiotic produced by submerged culture, which is widely used in medicine as a powerful inhibitor of β-lactamases, enzymes produced by bacteria resistant to antibiotics such penicillin and cephalosporin. The purpose of this work was to select the best clavulanic acid producer among strains of Streptomyces belonging to the Microorganism Collection of the Department of Antibiotics of the Federal University of Pernambuco (DAUFPE). Initially, the strains were studied for their capacity to inhibit the action of β-lactamases produced by Klebsiella aerogenes ATCC 15380. From these results, five strains were selected to investigate the batch kinetics of growth and clavulanic acid production in submerged culture carried out in flasks. The results were compared with the ones obtained by Streptomyces clavuligerus ATCC 27064 selected as a control strain. The best clavulanic acid producer was Streptomyces DAUFPE 3060, molecularly identified as Streptomyces variabilis, which increased the clavulanic acid production by 28% compared to the control strain. This work contributes to the enlargement of knowledge on new Streptomyces wild strains able to produce clavulanic acid by submerged culture.


Assuntos
Ácido Clavulânico/metabolismo , Inibidores Enzimáticos/metabolismo , Streptomyces/isolamento & purificação , Streptomyces/metabolismo , Enterobacter aerogenes/enzimologia , Programas de Rastreamento , Streptomyces/crescimento & desenvolvimento , beta-Lactamases/metabolismo
3.
Braz. j. microbiol ; 45(2): 743-751, Apr.-June 2014. ilus, tab
Artigo em Inglês | LILACS | ID: lil-723113

RESUMO

The use of low cost agro-industrial residues for the production of industrial enzymes is one of the ways to reduce significantly production costs. Cellulase producing actinomycetes were isolated from soil and decayed agricultural wastes. Among them, a potential culture, strain NEAE-J, was selected and identified on the basis of morphological, cultural, physiological and chemotaxonomic properties, together with 16S rDNA sequence. It is proposed that strain NEAE-J should be included in the species Streptomyces albogriseolus as a representative of a novel sub-species, Streptomyces albogriseolus subsp. cellulolyticus strain NEAE-J and sequencing product was deposited in the GenBank database under accession number JN229412. This organism was tested for its ability to produce endoglucanase and release reducing sugars from agro-industrial residues as substrates. Sugarcane bagasse was the most suitable substrate for endoglucanase production. Effects of process variables, namely incubation time, temperature, initial pH and nitrogen source on production of endoglucanase by submerged fermentation using Streptomyces albogriseolus subsp. cellulolyticus have been studied. Accordingly optimum conditions have been determined. Incubation temperature of 30 ºC after 6 days, pH of 6.5, 1% sugarcane bagasse as carbon source and peptone as nitrogen source were found to be the optimum for endoglucanase production. Optimization of the process parameters resulted in about 2.6 fold increase in the endoglucanase activity. Therefore, Streptomyces albogriseolus subsp. cellulolyticus coud be potential microorganism for the intended application.


Assuntos
Celulase/isolamento & purificação , Celulase/metabolismo , Streptomyces/metabolismo , Técnicas de Tipagem Bacteriana , Análise por Conglomerados , Carboidratos/análise , Celulose/metabolismo , Meios de Cultura/química , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Filogenia , /genética , Análise de Sequência de DNA , Saccharum/metabolismo , Streptomyces/classificação , Streptomyces/crescimento & desenvolvimento , Streptomyces/isolamento & purificação , Temperatura , Fatores de Tempo
4.
Braz. j. microbiol ; 42(3): 868-877, July-Sept. 2011. ilus, tab
Artigo em Inglês | LILACS | ID: lil-607515

RESUMO

The aim of this study was to isolate novel enzyme-producing bacteria from vegetation samples from East Antarctica and also to characterize them genetically and biochemically in order to establish their phylogeny. The ability to grow at low temperature and to produce amylases and proteases cold-active was also tested. The results of the 16S rRNA gene sequence analysis showed that the 4 Alga rRNA was 100 percent identical to the sequences of Streptomyces sp. rRNA from Norway and from the Solomon Islands. The Streptomyces grew well in submerged system at 20ºC, cells multiplication up to stationary phase being drastically increased after 120 h of submerged cultivation. The beta-amylase production reached a maximum peak after seven days, while alpha-amylase and proteases were performing biosynthesis after nine days of submerged cultivation at 20ºC. Newly Streptomyces were able to produce amylase and proteases in a cold environment. The ability to adapt to low temperature of these enzymes could make them valuable ingredients for detergents, the food industry and bioremediation processes which require low temperatures.


Assuntos
Amilases , Microbiologia Ambiental , RNA Bacteriano/análise , Streptomyces/crescimento & desenvolvimento , Streptomyces/isolamento & purificação , beta-Amilase/análise , Métodos , Filogenia , Métodos
5.
Artigo em Inglês | IMSEAR | ID: sea-16515

RESUMO

BACKGROUND & OBJECTIVE: Dermatophytes responsible for causing dermatophytoses in humans have acquired resistance to certain antimycotic drugs. We isolated naturally occurring actinomycetes with an ability to produce metabolites having antimycotic property. The timecourse of antifungal metabolite production in terms of arbitrary units (AU) under optimum conditions was studied. METHODS: Water and soil samples were collected from various locations. The actinomycetes were isolated on starch casein medium and screened for their antifungal activity against yeasts and molds including dermatophytes. One promising isolate which showed a unique, stable and interesting property of inhibiting only dermatophytes was selected and characterized. Optimization of antifungal metabolite production in terms of AU using Trichphyton rubrum as target was done. The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) values of the culture supernatant from the isolate and that of griseofulvin were determined for all dermatophytes. RESULTS: Of the 218 actinomycete isolates, 14 per cent produced the metabolites having antifungal activity. The selected actinomycete, identified as Streptomyces rochei AK 39 produced metabolite, which was active against only dermatophytes whereas yeasts and other molds were resistant to it. Starch casein medium was found to be good for inducing antifungal activity in the isolate. The maximum antifungal metabolite production (400 AU/ml) was achieved in the late log phase, which remained constant during the stationery phase, and it was extracellular in nature. The MIC and MFC values of the culture supernatant from the isolate against the dermatophytes were within the range 1.25 to 5 and 1.25 to 10 AU/ml respectively. INTERPRETATION & CONCLUSION: The metabolite from Streptomyces rochei AK 39 was produced during late log phase and was active against only dermatophytes with a greater potency than griseofulvin. However, this needs further investigation using purified powdered form of the active component.


Assuntos
Actinobacteria/crescimento & desenvolvimento , Antibacterianos/metabolismo , Arthrodermataceae/efeitos dos fármacos , Dermatomicoses/tratamento farmacológico , Farmacorresistência Fúngica , Griseofulvina/farmacologia , Humanos , Testes de Sensibilidade Microbiana , Microbiologia do Solo , Streptomyces/crescimento & desenvolvimento , Microbiologia da Água
6.
Indian J Exp Biol ; 2004 Sep; 42(9): 928-32
Artigo em Inglês | IMSEAR | ID: sea-63364

RESUMO

About 312 actinomycetes were isolated from soil samples on chitin agar. All these isolates were purified and screened for their antifungal activity against pathogenic fungi. Out of these, 22% of the isolates exhibited activity against fungi. One promising isolate with strong antifungal activity against pathogenic fungi was selected for further studies. This isolate was from Pune, and was active against both yeasts and molds. Various fermentation parameters were optimized. Based on morphological and biochemical parameters, the isolate was identified as Streptomyces. The correlation of antifungal activity with growth indicated growth dependent production of antimetabolite. Maximum antifungal metabolite production (600 units/ml) was achieved in the late log phase, which remained constant during stationery phase, and it was extracellular in nature.


Assuntos
Actinobacteria/crescimento & desenvolvimento , Antibiose , Antifúngicos/farmacologia , Fungos/efeitos dos fármacos , Testes de Sensibilidade Microbiana/métodos , Solo/análise , Microbiologia do Solo , Streptomyces/crescimento & desenvolvimento
7.
Mem. Inst. Oswaldo Cruz ; 94(6): 763-70, Nov.-Dec. 1999.
Artigo em Inglês | LILACS | ID: lil-251336

RESUMO

Streptomyces alboniger ATCC 12461 grown in brain heart infusion (BHI) medium produced two extracellular serine-proteinases, denoted SP I and SP II, which were purified by ammonium sulfate precipitation and aprotinin-agarose affinity chromatography. SP I was purified 88,9-fold and SP II 66,7- fold, with 33.4 percent and 10.4 percent yield, respectively. The optimum pH for the proteinases activity, using a-N-p-tosyl-L-arginine-methyl ester (TAME) as substrate, was 9-10 and the optimum temperature was 37ºC. The proteolytic activity of SP I and SP II was inhibited by aprotinin and SP I was partially inhibited by leupeptin, both serine-proteinase inhibitors. S. alboniger growth in BHI-liquid medium decreased when 5 mg/ml, 10 mg/ml of aprotinin was used, being completely inhibited with 20 mg/ml and 40 mg/ml. At the ultrastructural level, aprotinin-treated S. alboniger cells showed swelling of the bacterial body and condensation of the genetic material, probably related to the inhibition of its growth


Assuntos
Aprotinina/metabolismo , Serina Endopeptidases/isolamento & purificação , Inibidores de Serina Proteinase/metabolismo , Streptomyces/enzimologia , Aprotinina , Cromatografia , Eletroforese em Gel de Poliacrilamida , Inibidores de Serina Proteinase , Streptomyces/efeitos dos fármacos , Streptomyces/crescimento & desenvolvimento , Streptomyces/ultraestrutura
8.
Indian J Exp Biol ; 1999 Oct; 37(10): 1031-3
Artigo em Inglês | IMSEAR | ID: sea-61856

RESUMO

Production of cephamycin c and clavulanic acid by Streptomyces clavuligerus was investigated using different media in shake flask condition. Highest cell growth (3.8 g/L) was observed in glycerol, sucrose, proline and glutamic acid (GSPG) medium. Although, GSPG medium supported maximum growth, it was least effective for the synthesis of both cephamycin and clavulanic acid. Yield of cephamycin and clavulanic acid was maximum in dextrin and K medium, respectively. High and low level of constituents of dextrin medium, affected production of both cephamycin and clavulanic acid. Biosynthesis of clavulanic acid was associated with production of cephamycin c.


Assuntos
Antibacterianos/biossíntese , Cefamicinas/biossíntese , Ácido Clavulânico/biossíntese , Meios de Cultura , Streptomyces/crescimento & desenvolvimento
9.
Hindustan Antibiot Bull ; 1997 Feb-Nov; 39(1-4): 64-71
Artigo em Inglês | IMSEAR | ID: sea-2262

RESUMO

To induce higher amount of antifungal antibiotic production by variation of cultural parameters has been studied. The maximum effectivity was found in sucrose as carbon source, peptone as nitrogen source and at pH 7.0. The effect of other selected factors were also evaluated in order to judge the variables that influenced antibiotic production.


Assuntos
Antifúngicos/biossíntese , Meios de Cultura , Fermentação , Concentração de Íons de Hidrogênio , Streptomyces/crescimento & desenvolvimento , Temperatura
11.
Hindustan Antibiot Bull ; 1995 Feb-Nov; 37(1-4): 37-43
Artigo em Inglês | IMSEAR | ID: sea-2266

RESUMO

A streptomycete strain D1.5 capable of producing broad spectrum antiobiotic was isolated from soil. The morphological, cultural, physiological and biochemical characters were studied, compared to known species and identified as Streptmoyces hygroscopicus. Antibiotic activity of the strain was tested against both Gram positive and negative bacteria as well as fungi. It exhibited complete resistance to beta-lactum antibiotics.


Assuntos
Antibacterianos/biossíntese , Meios de Cultura , Resistência Microbiana a Medicamentos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Lactamas , Microscopia Eletrônica de Varredura , Microbiologia do Solo , Esporos/ultraestrutura , Streptomyces/crescimento & desenvolvimento
12.
Egyptian Journal of Microbiology. 1995; 30 (3): 355-68
em Inglês | IMEMR | ID: emr-95757

RESUMO

Highest production of alkaline protease by Streptomyces venezulae DSM 4027 was obtained with Vintsyunaite medium [1969] when used among five media tested. The effect of some factors such as inoculum, incubation temperature, air- medium ratio, pH of medium, carbon sources and nitrogen sources on alkaline protease production in Vintsyunaite medium by the shake culture method was investigated. Result could be summarized in the followings: Highest enzyme production was obtained when use 40 mg vegetative cells [2 days old inocula] when the culture was incubated at 30 for 6 days. The pH value for enzyme production was pH 7.0. The highest level of enzyme production could be obtained when starch or maltose at 4% final concentration was used as source of carbon in medium and upon use of soybean flour and ammonium sulphate as nitrogen sources to give 0.07% N final concentration. Some factors affecting crude proteases activity were also determined. The highest enzyme activity was expressed at: 50§ss an optimum temperature after 20 min. Incubation time at pH 9.0


Assuntos
Streptomyces/isolamento & purificação , Streptomyces/crescimento & desenvolvimento
13.
Egyptian Journal of Microbiology. 1995; 30 (3): 383-99
em Inglês | IMEMR | ID: emr-95759

RESUMO

Pyruvate kinase of Streptorrlyccs sparocinereus had a maximum activity at 40 and pH 8.0. Km value was 1.0 uM. It was activated by the addition of Mg SO4, KC1, Mg SO4, Ni 504, CoSO4, Hg C12 to the reaction mixture and inhibited by citrate, succinate, L-alanine and glutamate. Complete desiattuation occurred within few minutes with the exposure to acidic pH, while the enzyme was inactivated at pH7.0 and pH9.0 after 45 and 30 min respectively. Exposure of the enzyme to 50§ caused complete inactivation within few minutes, and it was rapidly inactivated when incubated at 40§. Some nucleocides revealed an increase in the activity of the enzyme such as AMP, GMP and CMP while others like ATP caused inhibition to the enzyme activity


Assuntos
Streptomyces/enzimologia , Streptomyces/crescimento & desenvolvimento
14.
Egyptian Journal of Microbiology. 1995; 30 (1): 19-35
em Inglês | IMEMR | ID: emr-37047

RESUMO

Cell-free extracts of some actinomycetes were found to contain some transaminases enzymes. Streptomyces nitrosporeus was selected as the most inducer for L-alanine-glycine and L-alanine glutamate transaminases. The first enzyme catalyzes the formation of pyruvate and lycine from L-alanine and glyoxylate, while the second enzyme catalyzes the formation of pyruvate and L-glutamate from L-alanine and alpha-ketoglutarate. The reversibility of the two reactions was demonstrated. The optimum activity of the first enzyme occurred at pH 7.5, while that of the second enzyme occurred at pH 8.0. The optimum temperature of the two enzymes was 40C. The temperature activity profiles and heat inactivation kinetics of the two enzymes were different, so the two reactions seem catalyzing by two different enzymes. The Km values for all substrate were calculated. The activity of the two enzymes was stimulated by the addition of pyridoxal phosphate, and was inhibited by the addition of hydroxylamine. The inhibition by hydroxylamine was overcome by pyridoxal phosphate. Stability of the two enzymes was studied. Dialysis for 24 hours against 0.02 M phosphate buffer pH 8.0, completely inhibited the activity of the two enzymes


Assuntos
Streptomyces/crescimento & desenvolvimento , Alanina
15.
Egyptian Journal of Microbiology. 1995; 30 (1): 53-65
em Inglês | IMEMR | ID: emr-37049

RESUMO

The chitinolytic activity of 10 Streptomyces strains was studied. Among them only three strains showed high chitinolytic activity on chitin mineral medium. S. Cellulose [F-2] exerted the highest chitinolytic activity. Data revealed that the maximal yield of inducible chitinase from this strain could be obtained by growing it on chitin-mineral medium, containing [w/v]: 1.5% colloidal chitin [dry weight], 0.01% yeast extract, 0.07% FeSO4, 7H2O and 0.001% ZnSO4, 7H2O which was initially adjusted to pH 7.0 and rate of aeration equal to 12.1 mg O2/L/min [50 ml medium/250 ml flask], inoculated by 2% [v/v] of homogenized spore suspension [containing approximately 2 x 106 spores ml-1] of seven-day-old culture and incubated at 28-30C for seven days under submerged culture condition. The antifungal activity of S. Cellulose [F-2] culture filtrate was also studied


Assuntos
Streptomyces/crescimento & desenvolvimento
16.
Egyptian Journal of Microbiology. 1995; 30 (1): 67-83
em Inglês | IMEMR | ID: emr-37050

RESUMO

The chitinase enzyme of Streptomyces cellulose [F-2] was purified 18.06-fold with overall yield of 23.7% of the original activity [cell free filtrate] and specific activity 294.3 units/mg protein by ammonium sulfate fractionation [60-80% saturation], ion-exchange chromatography, [DEAE-Cellulose] and sephadex G-200 gel filtration. The enzyme was characterized by demonstration of optimum activity at 35C and pH 7.0. It was stable at 35C and pH 7.0. The enzyme activity was slightly stimulated by Ca2+, Zn2+, Mg2+, Mn2+ and Fe2+ ions, but Na+ and K+ ions did not exert any effect on the enzyme activity which was inhibited by Cu2+, Hg2+, Ag+ ions as well as EDTA, Na- azide, L-cysteine, KCN, iodine, KMnO4 and iodoacetic acid. Addition of 1.5% [w/v] substrate [colloidal chitin] to the purified enzyme liquor led to complete stabilization of the enzyme when stored at 4C [refrigerator] for a period extended to 180 days and for a period of 35 days at room temperature. The antifungal activity of the purified chitinase enzyme was also studied


Assuntos
Streptomyces/crescimento & desenvolvimento
17.
Rev. cuba. farm ; 28(2): 82-9, jul.-dic. 1994. ilus
Artigo em Espanhol | LILACS | ID: lil-158523

RESUMO

Con una cepa de Streptomyces verticillus S 126, se estudió la síntesis de bleomicina y se analizaron diferentes parámetros del proceso fermentativo. Se establecieron las mejores condiciones de inóculo, así como un medio de producción constituido por harina de soya, almidón, licor de remojo de maíz y sales minerales, a nivel de zaranda rotatoria y fermentadores de 7 y 15 L. Para conocer la dinámica de 3 enzimas que intervienen en dicho proceso, se discute el comportamiento de la proteinasa neutra, la fosfatasa alcalina y la amilasa. La actividad antibiótica de los caldos de fermentación se determinó por el método de difusión en agar frente al Bacillus subtilis ATCC 6633


Assuntos
Meios de Cultura , Streptomyces/enzimologia , Streptomyces/crescimento & desenvolvimento , Fosfatase Alcalina/metabolismo , Amilases/metabolismo , Fermentação , Endopeptidases/metabolismo
18.
Egyptian Journal of Microbiology. 1994; 29 (2): 165-74
em Inglês | IMEMR | ID: emr-32244

RESUMO

Twenty-four of Streptomyces isolated from Egyptian soil samples were tested for the production of glucose isomerase. Streptomyces NRC-718 was closely related to Streptomyces canus according to the morphology, cultural and physiological properties was the highest producer of glucose isomerase among other tested strains. The enzyme was extracted from cells suspension ultrasonically. D-xylose served as substrate for the enzyme and the value of specific activity was 2.35 units/mg protein


Assuntos
Streptomyces/crescimento & desenvolvimento
20.
Egyptian Journal of Microbiology. 1993; 28 (1): 23-32
em Inglês | IMEMR | ID: emr-95517

RESUMO

effect of some nutritional factors on gelatinase biosyn-thesis by Streptomyces spheroides was studied. The experimental organism was cultivated at static conditions at 30° and pH 7.0 for 8 days. Starch-nitrate medium was used throughout this work. 0.3% gelatin gave the maximum gelatinase activity among the tested organic and inorganic nitrogen sourced, whereas 2.5% glucose and potassium dibasic phosphate [0.15%] were the most suitable carbon and phosphorus sources, respectively; for gelatinase biosynthesis. The effect of different calcium carbonate concentrations was also tested, 0.1% was the best concentration for gelatinase biosynthesis by Streptomyces spheroides


Assuntos
Streptomyces/crescimento & desenvolvimento
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