Studies on the asparaginolytic activity of the brown-pigmented streptomycetes

Twenty-eight brown-pigmented streptomycetes were isolated from different fertile Egyptian soils. Screening was carried out according to their asparaginolytic activity under static culture condition on glycerol- L-asparagine [GA] medium. Results revealed that FS-39 isolate gave the highest asparaginolytic activity. Therefore, it was selected and subjected to complete identification. The cultural, morphological and physiological characteristics of this isolate indicated that it belongs to Streptomyces phaeochromogenes. The effects of nutritional and environmental conditions on the asparaginase activity of Streptomyces phaeochromogenes FS-39 were studied. Data revealed that the maximal, yield of L-asparaginase from this strain can be obtained by growing it on glycerol-L-asparagine yeast extract [GAY] medium containing [w/v] 2.0% Glycerol, 0.2% L-asparagine, 0.1% yeast extract, 0.1% K[2]HPO[4].3H20, 0.0001% FeSO[4].7H[2]0, 0.0001% MnCl[2]. 4H[2]0, 0.0001% ZnSO[4].7H[2]O which was initially adjusted to pH 7.0, inoculated by 2% [v/v] of homogenized spore suspension [containing approximately 3.2x10[7] spores/ml] of 3 days old culture on starch nitrate medimi and incubated at 30°C for 7 days under static culture condition

Puriffication and characterization of L-asparaginase produced by Streptomyces phaeochromogenes FS-39

An L-asparaginase [EC.3.5.1.1] produced by Streptomyces phaeochromogenes FS-39 was purified and characterized. After initial ammonium sulfate fractionation [50-70% saturation], the enzyme was purified by consecutive column chromatography on ion exchange [DEAE-Cellulose] and Sephadex G-200 filtration. The 67.2 fold purified enzyme thus obtained has the specific activity of 179.14 units mg protein super [-1] with an over all recovery of 17.7%. The enzyme was characterized by demonstration of optimum activity at 35°C and pH 8.5. It was stable for 180 min. at 30-35°C and 7 days at 4°C [refrigerator] and pH range from 8.0 to 9.0. The enzyme activity was slightly stimulated by Mg supper [2+], Fe super [2+] and Ca super [2+] cations, but Na-azid and EDTA did not exert any effect on the enzyme activity. Hg super [2+], Ag super [+] and Cu super [2 +] cations as well as L-cysteine, iodine, KCN and iodoacetic acid strongly inhibited the enzyme, but Zn super [2+], KMnO4 and super [2+] potentially slightly inhibited the enzyme activity. L-aspartic acid was competitive inhibitor

Studies on the asparaginolytic enzymes of streptomycetes. I-Culture conditions for the production of L-asparaginase enzyme from streptomyces longsporusflavus [F-15] strain

Asparaginolytic activity of seven streptomyces strains was studied under static culture condition on glycerol-L-asparagine [GA] medium. Streptomyces longsporusflavus [F-15] only showed the highest asparagenolytic activity. Data revealed that the maximal yield of L-aspara- ginase from this strain can be obtained by growing it on starch-L-asparagine-yeast extract [SAY] medium, containing [W/V]: 1.5% starch, 0.2% L-asparagine, 0.05% yeast extract, 0.1% K2HP04.3H2O, 0.0001% FeSO4.7H2.0,0.0001% MnC12.4H2O,0001% ZnSO4 71120 which was initially adjusted to pH 7.0, inoculated by 2% [VM of homogenized spore suspension [containing approximately 2.5 x 10[6] spores/ml] of 4 days old culture on starch nitrate medium and incubated at 30§ for 5 days, under static culture condition

Studies on the chitinolytic enzymes of Streptomycetes 1- Culture conditions for the production of chitinase enzyme from a chitin-degrading Streptomyces cellulosae [F-2] strain

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

Studies on the proteolytic enzymes of S cellulosae [F-2] and S longsporusflavus [F-15]

The effect of medium composition on proteinase production by S. cellulosae [F-2] and S. longsporusflavus [F-15] was studied under submerged culture condition. Data revealed that starch-soybean meal [1.5% starch and 1.2% soybean meal] and wheat bran-peptone [4.4% wheat bran and 0.5% peptone] can be used as suitable and economical media for the maximal proteinase activity by S. cellulosae [F-2] and S. longsporusflavus [F-15], respectively. The optimal environmental conditions for maximal proteinase production by both strains in the suitable medium for each were determined to be as follows: 50 ml medium/250 ml flask, which initially adjusted to pH 7.0, inoculated by 2% [V/V] of homogenized spores suspension of 5-day old culture [1 ml of spore suspension containing approximately 2 x 106 spores] and incubated at 30C for 5 days. Some properties of the crude enzymes solution were studied. Results revealed that maximal activity of crude enzyme solution of S. cellulosae [F-2] was obtained at pH 6.0 and 30C, while the maximal activity of crude enzymes solution of S. longsporusflavus [F-15] was obtained at pH 8 and 40C. The effect of some metal salts and some inhibitors on the proteinase activity of both enzymes were also studied

Purification and properties of penicillinase enzymes from bacillus cereus and pseudomonas fluorescence

The inducible penicillinases from Bacillus cereus and Pseudomonas fluorescens can be obtained by growing them on nutrient broth medium supplemented with 1 mg/ml penicillin G [Na] adjust to initial pH 6.0 and rate of aeration equal to 5.5 mg O2/L/min [50 ml medium/450 ml flask] inoculated by 2% [V/V] of 2 days old culture [1 ml of bacterial suspension containing approximately 106 colony forming units] and incubated for 30 hr at 34C and 28C, respectively. Penicillinase of B. cereus was purified 338.9-fold with overall yield of 27.73% of the original activity and specific activity 215.2 units/mg protein, by ammonium sulfate precipitation, ion exchange chromatography [DEAE-cellulose] and Sephadex G-200 gel filtration. Also, penicillinase of Ps. fluorescens was purified 385.2-fold with overall yield of 30.0% of the original activity and specific activity 277.35 units/mg protein by using the same technique. Maxima activities of these two enzymes were obtained at 30C and pH 6.0. Also, both enzymes showed much greater activity against penicillins than against cephalosporins. The effect of some inhibitors [salts, chemical reagents and antibiotics] on the inhibition of these two enzymes was studied. Data revealed that both enzymes were inhibited to different degrees, ranging from 24.0% to 100.0% of the original activity, by preincubation for one hour with each inhibitor at different concentrations. Also, data revealed that a combination of penicillin G [Na] and cloxacillin or clavulanic acid improved markedly its activity against penicillinase producing strains of Bacillus cereus and Pseudomonas fluorescens distributed in Nile water and treated drinking water

Chemical nature of antibiotic produced by pseudomonas fluorescens strain a inhibiting azospirillum spp growth

The antagonistic activity of three Pseudomonas fluorescens strains against Azospirillum spp. was investigated. Data revealed that Pseudomonas fluorescens strain A was the most potent against Azospirillum lipoferum when grown on 523 agar medium, with initial pH of 7.0 and incubation for one day at 30C. Extraction of Pseudomonas fluorescens strain A active ingredient was achieved by using acetone followed by diethyl ether. Using paper chromatography technique, an antibiotic was obtained as purified yellowish brown amorphous powder. It is soluble in methanol, acetone, ethyl acetate, n-butanol, diethyl ether and chloroform. The physicochemical characteristics, i.e., melting point, ultraviolet spectra [UV], infrared spectra [IR], color reactions, the 1H nuclear magnetic resonance [1H-NMR], mass spectra and elemental analysis are given. The purified antibiotic exerted a sharp melting point at 126C, the UV absorption spectra was maximum at 245 [sh] nm in ethylacetate, the molecular weight was found to be 279. Relative abundance [RA], 9.9% and elemental analysis of the antibiotic revealed that the antibiotic substance contains carbon 81.7%, hydrogen 7.5%, oxygen 5.7% and nitrogen 5.0%. The molecular formula of the antibiotic was proposed to C19H21NO based on the MS spectra and elemental analysis

Effect of subminimal inhibitory concentrations of clindamycin, streptomycin, chloramphenicol, erythromycin and clavulanic acid on the penicillinase production of Staphylococcus aureus, Bacillus cereus and Pseudomonas fluorescens

The influence of subminimal inhibitory concentrations of clindamycin, streptomycin, chloramphenicol, erythromycin and clavulanic acid on the penicillinase production of Staphylococ-cus aureus, Bacillus cereus and Pseudomonas fluorescens were tested. Results revealed that the penicillinase activity can be inhibited by subminimal inhibitory concentrations of these antibiotics. The maximal inhibitory effect was generally induced by concentrations ranging from 1/2 to 1/32 the minimal inhibitory concentrations of clmdamycin and clavulanic acid. Results also revealed that the clindamycin or clavulanic acid produced synergy when combined with penicillin G [Na] against three strains tested in vitro

Studies on two locally isolated streptomyces species with antifungal activity

The study of antifungal activity of 114 of streptomycetes isolates, revealed that isolates No. W-2and W-5 exerted the highest antifungal activities against Fusarium oxysporium, Aspergillus parasiticus and Aspergillus niger. The cultural, morphological and physiological characteristics of both isolates indicated that they belong to Streptomyces californicus and Streptomyces prunicolor. The effect of the medium composition on their antagonistic activity was also studied