scholarly journals Crystal structure of thermostable alkylsulfatase SdsAP from Pseudomonas sp. S9

2017 ◽  
Vol 37 (3) ◽  
Author(s):  
Lifang Sun ◽  
Pu Chen ◽  
Yintao Su ◽  
Zhixiong Cai ◽  
Lingwei Ruan ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Sodium Dodecyl ◽  
Titration Calorimetry ◽  
Pseudomonas Sp ◽  
Sterol Carrier Protein ◽  
Dimerization Domain ◽  
Alkyl Chains ◽  
Hydrolysis Of

A novel alkylsulfatase from bacterium Pseudomonas sp. S9 (SdsAP) was identified as a thermostable alkylsulfatases (type III), which could hydrolyze the primary alkyl sulfate such as sodium dodecyl sulfate (SDS). Thus, it has a potential application of SDS biodegradation. The crystal structure of SdsAP has been solved to a resolution of 1.76 Å and reveals that SdsAP contains the characteristic metallo-β-lactamase-like fold domain, dimerization domain, and C-terminal sterol carrier protein type 2 (SCP-2)-like fold domain. Kinetic characterization of SdsAP to SDS by isothermal titration calorimetry (ITC) and enzymatic activity assays of constructed mutants demonstrate that Y246 and G263 are important residues for its preference for the hydrolysis of ‘primary alkyl’ chains, confirming that SdsAP is a primary alkylsulfatase.

scholarly journals Purification and Characterization of 2,6-β-d-Fructan 6-Levanbiohydrolase fromStreptomyces exfoliatus F3-2

2000 ◽  
Vol 66 (1) ◽  
pp. 252-256 ◽  
Author(s):  
Katsuichi Saito ◽  
Kazuya Kondo ◽  
Ichiro Kojima ◽  
Atsushi Yokota ◽  
Fusao Tomita
Keyword(s):  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Extracellular Enzyme ◽  
Molecular Weights ◽  
Sds Page ◽  
Monomeric Structure ◽  
Ph Range ◽  
Hydrolysis Of

ABSTRACT Streptomyces exfoliatus F3-2 produced an extracellular enzyme that converted levan, a β-2,6-linked fructan, into levanbiose. The enzyme was purified 50-fold from culture supernatant to give a single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The molecular weights of this enzyme were 54,000 by SDS-PAGE and 60,000 by gel filtration, suggesting the monomeric structure of the enzyme. The isoelectric point of the enzyme was determined to be 4.7. The optimal pH and temperature of the enzyme for levan degradation were pH 5.5 and 60°C, respectively. The enzyme was stable in the pH range 3.5 to 8.0 and also up to 50°C. The enzyme gave levanbiose as a major degradation product from levan in an exo-acting manner. It was also found that this enzyme catalyzed hydrolysis of such fructooligosaccharides as 1-kestose, nystose, and 1-fructosylnystose by liberating fructose. Thus, this enzyme appeared to hydrolyze not only β-2,6-linkage of levan, but also β-2,1-linkage of fructooligosaccharides. From these data, the enzyme from S. exfoliatus F3-2 was identified as a novel 2,6-β-d-fructan 6-levanbiohydrolase (EC 3.2.1.64 ).

Characterization of peptidases of adult Trichuris muris

Parasitology ◽  
1994 ◽  
Vol 109 (5) ◽  
pp. 623-630 ◽  
Author(s):  
L. J. Drake ◽  
A. E. Bianco ◽  
D. A. P. Bundy ◽  
F. Ashall
Keyword(s):  
Mammalian Cells ◽  
Culture Medium ◽  
Matrix Protein ◽  
Sodium Dodecyl ◽  
Time Dependent ◽  
Extracellular Matrix Protein ◽  
Peptidase Activity ◽  
Trichuris Muris ◽  
Hydrolysis Of

Excretory/secretory (E/S) material of Trichuris muris was found to contain 2 major peptidases, Mr 85 and 105 kDa, which degrade gelatin optimally at pH 6·0 in sodium dodecyl sulphate–polyacrylamide gels. The peptidases were inactivated diisopropylfluorophosphate, leupeptin and soybean trypsin inhibitor, but were unaffected by inhibitors of aspartic-, cysteine- and metallo-peptidases, indicating that they are serine peptidases. Both enzymes were detectable within 5 h after incubation of worms in culture medium and showed a time-dependent increase in levels. Neither peptidase was detected in worm extracts, suggesting that they are activated during or following secretion from worms. Live worms degraded radio-isotope labelled extracellular matrix protein substratum derived from mammalian cells. Aminopeptidase activities capable of catalysing hydrolysis of amino acyl aminomethylcoumarin (MCA) substrates and a Z-Phe-Arg-MCA-hydrolysing cysteine peptidase activity, were detected in extracts of adult worms but not in E/S material.

Characterization of lactococci and lactobacilli isolated from semihard goats' cheese

1991 ◽  
Vol 58 (1) ◽  
pp. 137-145 ◽  
Author(s):  
Teresa Requena ◽  
Carmen Peláez ◽  
Michel J. Desmazeaud
Keyword(s):  
Leucine Aminopeptidase ◽  
Sodium Dodecyl ◽  
Skim Milk ◽  
Titratable Acidity ◽  
Aminopeptidase Activity ◽  
Whole Cells ◽  
Alanine Aminopeptidase ◽  
Triton X ◽  
Hydrolysis Of

SummarySeveral strains ofLactococcus lactissubsp.lactis, Lactobacillus caseiandLactobacillus plantarumisolated from traditional goats' cheese have been studied for titratable acidity, proteolysis in milk and enzymic activities. Aminopeptidasc activities were measured with whole cells and cells permeabilized with Triton X-100. Caseinolytic activity was investigated using electrophoresis in polyacrylamide gel with sodium dodecyl sulphate.Lc. lactissubsp.lactishad a level of proteolytic activity in skim milk greater than that ofLb. casei, while this activity inLb. plantarumwas very low. Alanine aminopeptidase activity was almost non-existent for all strains tested, while lysine aminopeptidase activity appeared to be of fundamentally intracellular origin. Leucine aminopeptidase activity was also greater in cells that had been permeabilized than in whole cells forLb. caseiandLb. plantarum. Lc. lactissubsp.lactisleucine aminopeptidase activity was greater in whole cells. No significant hydrolysis of casein was found withLb. caseiI FPL 725 andLb. plantarumIFPL 722 permeabilized with Triton X-100 after 24 h incubation with whole bovine casein.

scholarly journals Identification and Characterization of CAMP Cohemolysin as a Potential Virulence Factor of Riemerella anatipestifer

2002 ◽  
Vol 184 (7) ◽  
pp. 1932-1939 ◽  
Author(s):  
Karen C. Crasta ◽  
Kim-Lee Chua ◽  
Sumathi Subramaniam ◽  
Joachim Frey ◽  
Hilda Loh ◽  
...  
Keyword(s):  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Chromosomal Dna ◽  
Pcr Cloning ◽  
Reading Frame ◽  
E Coli ◽  
Recombinant Plasmids ◽  
Riemerella Anatipestifer ◽  
Hydrolysis Of

ABSTRACT Riemerella anatipestifer is responsible for exudative septicemia in ducks. The genetic determinant of the CAMP cohemolysin, cam, from a strain of R. anatipestifer was cloned and expressed in Escherichia coli. Chromosomal DNA from serotype 19 strain 30/90 was used to construct a gene library in pBluescript II SK(−) vector in E. coli XL-1-Blue strain. The clones containing recombinant plasmids were screened for the CAMP reaction with Staphylococcus aureus. Those that showed cohemolysis were chosen for further analysis by sequencing. One of these clones, JFRA8, was subcloned to identify the smallest possible DNA fragment containing the CAMP cohemolysin determinant, which was located on a 3,566-bp BamHI-BstXI fragment which specified a 1,026-bp open reading frame. Clones containing recombinant plasmids carrying cam obtained by PCR cloning into E. coli M15 strain secreted an active CAMP cohemolysin. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blot analyses confirmed that the recombinant strain expressed a protein with a molecular mass of 37 kDa and that strains from serotypes 1, 2, 3, 5, 6, and 19 expressed the cohemolysin. The deduced amino acid sequence showed high homology to those of O-sialoglycoprotein endopeptidases. Hydrolysis of radioiodinated glycophorin A confirmed that Cam is a sialoglycoprotease.

Purification and Characterization of an Unusual Aminopeptidase From Pea Seeds

1980 ◽  
Vol 7 (2) ◽  
pp. 131 ◽  
Author(s):  
JB Caldwell ◽  
LG Sparrow
Keyword(s):  
Molecular Weight ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Sulfhydryl Group ◽  
Purification And Characterization ◽  
Apparent Homogeneity ◽  
Pea Seeds ◽  
Hydrolysis Of

An aminopeptidase with specificity for N-terminal glutamic and aspartic acid residues has been purified to apparent homogeneity from pea seeds (Pisum sativum cv. Greenfeast). It also catalyses the hydrolysis of the glutaryl-phenylalanine bond of the synthetic chymotrypsin substrate glutaryl- L-phenylalanine p-nitroanilide. The native enzyme, which has a molecular weight of approximately 500 000, gives a single band on polyacrylamide gel electrophoresis but two major bands when subjected to electrophoresis in the presence of sodium dodecyl sulfate after reduction. Its behaviour with various inhibitors suggests that a sulfhydryl group is important for its activity.

Purification and characterization of an extracellular chitinase from the entomopathogen Metarhizium anisopliae

1997 ◽  
Vol 43 (4) ◽  
pp. 322-327 ◽  
Author(s):  
Alexandre de Siqueira Pinto ◽  
Cristine Chaves Barreto ◽  
Marilene Henning Vainstein ◽  
Augusto Schrank ◽  
Cirano José Ulhoa
Keyword(s):  
Metarhizium Anisopliae ◽  
Enzyme Purification ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Anion Exchange Chromatography ◽  
Enzyme Characterization ◽  
Exchange Chromatography ◽  
Optimum Ph ◽  
Hydrolysis Of

Chitinases are produced by Metarhizium anisopliae when it is grown in the presence of chitin. A chitinase from the culture filtrate of Metarhizium anisopliae was successively purified by precipitation with ammonium sulphate, followed by anion-exchange chromatography on DEAE-Sephacel. The purified enzyme, which has a molecular mass of approximately 30 kDa by sodium dodecyl sulphate – polyacrylamide gel electrophoresis, catalyses the hydrolysis of p-nitrophenyl β-N-diacetylchitobiose with an apparent Km of 0.537 mmol and Vmax of 4.86 nmol∙mL−1∙min−1. The optimum pH and temperature were 4.5–5.0 and 40–45 °C, respectively.Key words: chitinases, Metarhizium anisopliae, enzyme purification, enzyme characterization.

scholarly journals Cloning and Characterization of Lipase Gene from a Local Isolate of Pseudoxanthomonas sp.

2017 ◽  
Vol 14 (2) ◽  
pp. 503-507 ◽  
Author(s):  
Yogi Yopa Kristia ◽  
Syifa F Syihab ◽  
Akhmaloka Akhmaloka
Keyword(s):  
Crystal Structure ◽  
3D Structure ◽  
Catalytic Triad ◽  
Catalytic Residue ◽  
Pseudomonas Sp ◽  
Amino Acid Residues ◽  
Chromosomal Dna ◽  
Lipase Gene

ABSTRACT: Lipase gene from Pseudoxanthomonas sp. was cloned through in vitro amplification from total chromosomal DNA. The gene was sequenced and characterized, coding for 312 amino acid residues. Homological analysis showed that the gene has 98% similarity to lipolytic gene from Uncultured Pseudomonas sp (GenBank No. AKA58891.1). Further analysis appeared that the sequences showed similar unique motifs of lipase sub-family I.1, such as pentapeptide (GHSHG) motif, tetrapeptide (GMLG) motif, and catalytic triad. In additional, 3D structure analysis based on crystal structure of Pseudomonas aeruginose (PDB ID 1ex9) showed that both structure of lipases are similar except on the conformation of catalytic residue of His277 showing to shift more far away compared to that the control.

scholarly journals Purification and Characterization of an Inverting Stereo- and Enantioselective sec-Alkylsulfatase from the Gram-Positive Bacterium Rhodococcus ruber DSM 44541

2003 ◽  
Vol 69 (5) ◽  
pp. 2810-2815 ◽  
Author(s):  
Mateja Pogorevc ◽  
Kurt Faber
Keyword(s):  
Enzymatic Hydrolysis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Rhodococcus Ruber ◽  
Whole Cells ◽  
Enantiomeric Ratio ◽  
Alkyl Sulfates ◽  
Substrate Tolerance ◽  
Hydrolysis Of

ABSTRACT Whole cells of Rhodococcus ruber DSM 44541 were found to hydrolyze (±)-2-octyl sulfate in a stereo- and enantiospecific fashion. When growing on a complex medium, the cells produced two sec-alkylsulfatases and (at least) one prim-alkylsulfatase in the absence of an inducer, such as a sec-alkyl sulfate or a sec-alcohol. From the crude cell-free lysate, two proteins responsible for sulfate ester hydrolysis (designated RS1 and RS2) were separated from each other based on their different hydrophobicities and were subjected to further chromatographic purification. In contrast to sulfatase RS1, enzyme RS2 proved to be reasonably stable and thus could be purified to homogeneity. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed a single band at a molecular mass of 43 kDa. Maximal enzyme activity was observed at 30°C and at pH 7.5. Sulfatase RS2 showed a clear preference for the hydrolysis of linear secondary alkyl sulfates, such as 2-, 3-, or 4-octyl sulfate, with remarkable enantioselectivity (an enantiomeric ratio of up to 21 [23]). Enzymatic hydrolysis of (R)-2-octyl sulfate furnished (S)-2-octanol without racemization, which revealed that the enzymatic hydrolysis proceeded through inversion of the configuration at the stereogenic carbon atom. Screening of a broad palette of potential substrates showed that the enzyme exhibited limited substrate tolerance; while simple linear sec-alkyl sulfates (C7 to C10) were freely accepted, no activity was found with branched and mixed aryl-alkyl sec-sulfates. Due to the fact that prim-sulfates were not accepted, the enzyme was classified as sec-alkylsulfatase (EC 3.1.6.X).

scholarly journals Biophysical characterization of two commercially available preparations of the drug containing Escherichia coli L-Asparaginase 2

2020 ◽  
Author(s):  
Talita Stelling de Araújo ◽  
Sandra M. N. Scapin ◽  
William de Andrade ◽  
Maira Fasciotti ◽  
Mariana T. Q. de Magalhães ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Active Site ◽  
Lymphoblastic Leukemia ◽  
Biophysical Characterization ◽  
E Coli ◽  
Terminal Loop ◽  
Hydrolysis Of

AbstractThe hydrolysis of asparagine and glutamine by L-asparaginase has been used to treat acute lymphoblastic leukemia for over four decades. Each L-asparaginase monomer has a long loop that closes over the active site upon substrate binding, acting as a lid. Here we present a comparative study two commercially available preparations of the drug containing Escherichia coli L-Asparaginase 2, performed by a comprehensive array of biophysical and biochemical approaches. We report the oligomeric landscape and conformational and dynamic plasticity of E. coli type 2 L-asparaginase (EcA2) present in two different formulations, and its relationship with L-aspartic acid, which is present in Aginasa, but not in Leuginase. EcA2 shows a composition of monomers and oligomers up to tetramers, which is mostly not altered in the presence of L-Asp. The N-terminal loop of Leuginase, which is part of the active site is flexibly disordered, but gets ordered as in Aginasa in the presence os L-Asp, while L-Glu only does so to a limited extent. Ion-mobility spectrometry–mass spectrometry reveals two conformers for the monomeric EcA2, one of which can selectively bind to L-Asp and L-Glu. Aginasa has higher resistance to in vitro proteolysis than Leuginase, and this is directly related to the presence of L-Asp.

Sign in / Sign up

Export Citation Format

Share Document