scholarly journals Purification and characterization of cephalosporin 7α-hydroxylase from Streptomyces clavuligerus

1991 ◽  
Vol 280 (2) ◽  
pp. 471-474 ◽  
Author(s):  
X Xiao ◽  
S Wolfe ◽  
A L Demain

Cephalosporin 7 alpha-hydroxylase, which catalyses the conversion of cephalosporins into their 7 alpha-hydroxy derivatives, was purified nearly 390-fold from Streptomyces clavuligerus through ion-exchange chromatography, (NH4)2SO4 fractionation, gel filtration and dye chromatography, with the use of h.p.l.c. to monitor enzyme activity. The nearly pure enzyme migrates as a single major band, with an Mr of 32,000 in SDS/PAGE. Its optimum pH is in the range 7.3-7.7. Under our conditions the reaction was fastest at temperatures in the range 20-30 degrees C. The Km for cephalosporin C is 0.72 mM, and the Vmax. is 15.4 mumol of cephalosporin C hydroxylated/min per mg. Cephalosporin 7 alpha-hydroxylase did not show any deacetoxycephalosporin C synthase or deacetoxycephalosporin C hydroxylase activity.

2013 ◽  
Vol 10 (3) ◽  
pp. 844-853
Author(s):  
Baghdad Science Journal

Endoglucanase produced from Aspergillus flavus was purified by several steps including precipitation with 25 % ammonium sulphate followed by Ion –exchange chromatography, the obtained specific activity was 377.35 U/ mg protein, with a yield of 51.32 % .This step was followed by gel filtration chromatography (Sepharose -6B), when a value of specific activity was 400 U/ mg protein, with a yield of 48 %. Certain properties of this purified enzyme were investigated, the optimum pH of activity was 7 and the pH of its stability was 4.5, while the temperature stability was 40 °C for 60 min. The enzyme retained 100% of its original activity after incubation at 40 °C for 60 min; the optimum temperature for enzyme activity was 40 °C.


1982 ◽  
Vol 47 (4) ◽  
pp. 1139-1148 ◽  
Author(s):  
Karel Hauzer ◽  
Linda Servítová ◽  
Tomislav Barth ◽  
Karel Jošt

Post-proline endopeptidase was isolated from pig kidneys and partially purified. The procedure consisted of fractionation with ammonium sulphate, ion exchange chromatography on DEAE-Sephadex A-50, gel filtration on Sephadex G-200 and rechromatography on DEAE-Sephadex A-50. The preparation had 55 times higher specific activity than the crude extract and did not contain any contaminating enzymic activities. The enzyme cleaved a number of proline-containing peptides and was strictly specific in catalyzing the hydrolysis of the peptide bond on the carboxyl side of the proline residue. The optimum pH for the hydrolysis of the synthetic peptides benzyl-oxycarbonylglycyl-prolyl-leucyl-glycinamide and benzyloxycarbonyl-glycyl-proline β-naphtylamide was 7.8-8.0 and, in the case of benzyloxycarbonylglycyl-proline p-nitroanilide, 7.2 to 7.5. For the hydrolysis of the tetrapeptide benzyloxycarbonylglycyl-prolyl-leucyl-glycinamide, the Km value of 75 μ mol l-1 was obtained.


Parasitology ◽  
2003 ◽  
Vol 126 (2) ◽  
pp. 155-163 ◽  
Author(s):  
A. SEIXAS ◽  
P. C. DOS SANTOS ◽  
F. F. VELLOSO ◽  
I. DA SILVA VAZ ◽  
A. MASUDA ◽  
...  

Here we describe the purification and characterization of a vitellin (VT) degrading cysteine endopeptidase (VTDCE) from eggs of the hard tick Boophilus microplus. A homogeneous enzyme preparation was obtained by chromatographic fractionation on ion-exchange and gel filtration columns and an autolysis step. This step consisted of incubation of a semipurified enzyme (after the first ion-exchange chromatography) at pH 4·0 that dissociated the enzyme from VT, to which VTDCE is naturally tightly associated. The enzyme purity was confirmed by capillary and native gel electrophoresis, and SDS–PAGE suggested the enzyme is a dimer of 17 and 22 kDa. VTDCE was active upon several synthetic substrates, with a preference for a hydrophobic or a basic residue in P1, and a hydrophobic residue in P2. VTDCE also hydrolysed haemoglobin, albumin, gelatin and vitellin. VTDCE is inactive in the absence of DTT and was totally inhibited by E-64, indicating it is a cysteine endopeptidase. Our results suggest that VTDCE is a major enzyme involved in yolk processing during B. microplus embryogenesis.


2013 ◽  
Vol 773 ◽  
pp. 336-341 ◽  
Author(s):  
Wen Ge Yu ◽  
Bei Bei Zhang ◽  
Yong Jian Shen ◽  
Ying Li ◽  
Yong Bin Tian ◽  
...  

In this paper, the superoxide dismutase fromMartianus dermestoidesis purified by the following methods: heat treatment, polyethylene concentration, Sephadex G-75 gel filtration, and DEAE-Sepharose FF ion exchange chromatography. The result shows that the purification multiple is 3.86, the activation yield is 21.89% and the specific activation of the enzyme is 447.6 U/mg. The purified SOD appears to be a sole protein on SDS-PAGE and the molecular weight is estimated to be 40.58 kDa. H2O2can obviously inhibit the enzyme activation and CHCl3-CH3CH2OH only demonstrates basically no inhibitory effect. The type of the dermestoides SOD might be Cu/Zn-SOD. After purification, some enzymatic characterizations of the SOD are studied. The optimum reaction temperature of purified SOD is 50°C. The optimum reaction pH value of purification is 6. The dermestoide SOD has a preferable stability below 50°C and at pH values between 5-8.


2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Mohsen Helmy Selim ◽  
El-Zahraa Karm Eldin ◽  
Moataza Mahmoud Saad ◽  
El-Sayed Eliwa Mostafa ◽  
Yosrea Hassan Shetia ◽  
...  

The aim of the present study is to purify L-methioninase from Candida tropicalis 34.19-fold with 27.98% recovery after ion exchange chromatography followed by gel filtration. The purified enzyme revealed a single band on SDS-PAGE gel with a molecular weight of 46 KDa. Its optimum temperature was 45 to 55 and thermal stability was 55°C for 15 min. The enzyme had optimum pH at 6.5 and stability at a pH range of 5.5 to 7.0 for 24 hr. The maximum activity was observed with substrate concentration of 30 µM and Km was 0.5 mM. The enzyme was strongly inhibited by Cd+2 and Cu+2 while it was enhanced by Na+, Ni+2, and Mg+2 at 10 mM while Ca+2 had slight activation at 20 mM. In addition, the potential application of the L-methioninase as an anticancer agent against various types of tumor cell lines is discussed.


HortScience ◽  
1992 ◽  
Vol 27 (6) ◽  
pp. 653f-653
Author(s):  
Seung-Ryeul Shin ◽  
Jae-Kyun Byun ◽  
Kyung-Ho Chang

β-Galactosidase was purified from apple, Malus domestica Borkh, cv. Fuji by gel filtration, CM cellulose ion exchange chromatography, and characterizied by means of several biochemical methods. One form of β-Galactosidase was detected and the Km and Vmax values were calculated to be 0.035 and 0.036 mM with para-nitrophenyl-β-D-galactoside lmM/15min., respectively. The β-galactosidase was active between pH 3 and 7 with the optimum pH of about 4-5. The stable temperature for β-galactosidase was lower than 45°C with 30°C optimum. The β-galactosidase activities were inhibited by Ag*. EDTA and SDS.


1992 ◽  
Vol 288 (2) ◽  
pp. 475-482 ◽  
Author(s):  
I Ishii-Karakasa ◽  
H Iwase ◽  
K Hotta ◽  
Y Tanaka ◽  
S Omura

For the purification of a new type of endo-alpha-N-acetylgalactosaminidase from the culture medium of Streptomyces sp. OH-11242 (endo-GalNAc-ase-S) [Iwase, Ishii, Ishihara, Tanaka, Omura & Hotta (1988) Biochem. Biophys. Res. Commun. 151, 422-428], a method for assaying enzyme activity was established. Using purified pig gastric mucus glycoprotein (PGM) as the substrate, oligosaccharides liberated from PGM were pyridylaminated, and the reducing terminal sugars of oligosaccharides larger than Gal beta 1-3GalNAc were analysed by h.p.1.c. The crude enzyme of endo-GalNAc-ase-S was prepared as an 80% (w/v) ammonium sulphate precipitate from the concentrated culture medium. The enzyme was partially purified by gel chromatofocusing and subsequent DEAE-Toyopearl chromatography. Endo-enzyme activity eluted around pI 4.8 on a gel chromatofocusing column and eluted with 0.19-0.25 M-NaCl on a DEAE-Toyopearl column. In the enzyme fraction obtained, no exo-glycosidases or proteases could be detected. The molecular mass of the enzyme was estimated as 105 kDa by gel filtration, and the optimum pH was 5.5. Endo-GalNAc-ase-S hydrolysed the O-glycosidic linkage between GalNAc and Ser (Thr) in 3H-labelled and unlabelled asialofetuin, liberating both the disaccharide (Gal beta 1-3GalNAc) and the tetrasaccharide [Gal beta 1-3 (Gal beta 1-4GlcNAc beta 1-6)GalNAc]. When endo-alpha-N-acetylgalactosaminidase from Alcaligenes sp. (endo-GalNac-ase-A) was incubated with 3H-labelled and unlabelled asialofetuin, only the disaccharide (Gal beta 1-3GalNAc) was liberated.


2017 ◽  
Vol 18 (2) ◽  
pp. 1-10 ◽  
Author(s):  
Dzun Noraini Jimat ◽  
Intan Baizura Firda Mohamed ◽  
Azlin Suhaida Azmi ◽  
Parveen Jamal

A newly bacterial producing L-asparaginase was successful isolated from Sungai Klah Hot Spring, Perak, Malaysia and identified as Bacillus sp. It was the best L-asparaginase producer as compared to other isolates. Production of L-asparaginase from the microbial strain was carried out under liquid fermentation. The crude enzyme was then centrifuged and precipitated with ammonium sulfate before further purified with chromatographic method. The ion exchange chromatography HiTrap DEAE-Sepharose Fast Flow column followed by separation on Superose 12 gel filtration were used to obtain pure enzyme. The purified enzyme showed 10.11 U/mg of specific activity, 50.07% yield with 2.21 fold purification. The purified enzyme was found to be dimer in form, with a molecular weight of 65 kDa as estimated by SDS-PAGE. The maximum activity of the purified L-asparaginase was observed at pH 9 and temperature of 60°C.


1999 ◽  
Vol 181 (1) ◽  
pp. 91-99 ◽  
Author(s):  
Hisayo Ono ◽  
Kazuhisa Sawada ◽  
Nonpanga Khunajakr ◽  
Tao Tao ◽  
Mihoko Yamamoto ◽  
...  

ABSTRACT 1,4,5,6-Tetrahydro-2-methyl-4-pyrimidinecarboxylic acid (ectoine) is an excellent osmoprotectant. The biosynthetic pathway of ectoine from aspartic β-semialdehyde (ASA), in Halomonas elongata, was elucidated by purification and characterization of each enzyme involved. 2,4-Diaminobutyrate (DABA) aminotransferase catalyzed reversively the first step of the pathway, conversion of ASA to DABA by transamination with l-glutamate. This enzyme required pyridoxal 5′-phosphate and potassium ions for its activity and stability. The gel filtration estimated an apparent molecular mass of 260 kDa, whereas molecular mass measured by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was 44 kDa. This enzyme exhibited an optimum pH of 8.6 and an optimum temperature of 25°C and had Km s of 9.1 mM forl-glutamate and 4.5 mM for dl-ASA. DABA acetyltransferase catalyzed acetylation of DABA to γ-N-acetyl-α,γ-diaminobutyric acid (ADABA) with acetyl coenzyme A and exhibited an optimum pH of 8.2 and an optimum temperature of 20°C in the presence of 0.4 M NaCl. The molecular mass was 45 kDa by gel filtration. Ectoine synthase catalyzed circularization of ADABA to ectoine and exhibited an optimum pH of 8.5 to 9.0 and an optimum temperature of 15°C in the presence of 0.5 M NaCl. This enzyme had an apparent molecular mass of 19 kDa by SDS-PAGE and a Km of 8.4 mM in the presence of 0.77 M NaCl. DABA acetyltransferase and ectoine synthase were stabilized in the presence of NaCl (>2 M) and DABA (100 mM) at temperatures below 30°C.


2005 ◽  
Vol 37 (6) ◽  
pp. 363-370 ◽  
Author(s):  
Ye-Yun Li ◽  
Chang-Jun Jiang ◽  
Xiao-Chun Wan ◽  
Zheng-Zhu Zhang ◽  
Da-Xiang Li

Abstractβ-Glucosidases are important in the formation of floral tea aroma and the development of resistance to pathogens and herbivores in tea plants. A novel β-glucosidase was purified 117-fold to homogeneity, with a yield of 1.26%, from tea leaves by chilled acetone and ammonium sulfate precipitation, ion exchange chromatography (CM-Sephadex C-50) and fast protein liquid chromatography (FPLC; Superdex 75, Resource S). The enzyme was a monomeric protein with specific activity of 2.57 U/mg. The molecular mass of the enzyme was estimated to be about 41 kDa and 34 kDa by SDS-PAGE and FPLC gel filtration on Superdex 200, respectively. The enzyme showed optimum activity at 50 °C and was stable at temperatures lower than 40 °C. It was active between pH 4.0 and pH 7.0, with an optimum activity at pH 5.5, and was fairly stable from pH 4.5 to pH 8.0. The enzyme showed maximum activity towards pNPG, low activity towards pNP-Galacto, and no activity towards pNP-Xylo.


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