scholarly journals Purification and preliminary characterization of alcohol dehydrogenase from Aspergillus nidulans

1985 ◽  
Vol 225 (2) ◽  
pp. 449-454 ◽  
Author(s):  
E H Creaser ◽  
R L Porter ◽  
K A Britt ◽  
J A Pateman ◽  
C H Doy
Keyword(s):  
Amino Acid ◽  
Alcohol Dehydrogenase ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Single Step ◽  
Activity Profile ◽  
Alcohol Dehydrogenases ◽  
Freeze Dried ◽  
Blue Sepharose

Aspergillus alcohol dehydrogenase is produced in response to growth in the presence of a wide variety of inducers, of which the most effective are short-chain alcohols and ketones, e.g. butan-2-one and propan-2-ol. The enzyme can be readily extracted from fresh or freeze-dried cells and purified to homogeneity on Blue Sepharose in a single step by using specific elution with NAD+ and pyrazole. The pure enzyme has Mr 290 000 by electrophoresis or gel filtration; it is a homopolymer with subunit Mr 37 500 by electrophoresis in sodium dodecyl sulphate; its amino acid composition corresponds to Mr 37 900, and the native enzyme contains one zinc atom per subunit. The enzyme is NAD-specific and has a wide substrate activity in the forward and reverse reactions; its activity profile is not identical with those of other alcohol dehydrogenases.

scholarly journals Biochemical and Genetic Characterization of an FK506-Sensitive Peptidyl Prolyl cis-trans Isomerase from a Thermophilic Archaeon, Methanococcus thermolithotrophicus

1998 ◽  
Vol 180 (2) ◽  
pp. 388-394 ◽  
Author(s):  
Masahiro Furutani ◽  
Toshii Iida ◽  
Shigeyuki Yamano ◽  
Kei Kamino ◽  
Tadashi Maruyama
Keyword(s):  
Amino Acid ◽  
Genomic Library ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Ppiase Activity ◽  
Methanococcus Thermolithotrophicus ◽  
Fk506 Binding Protein ◽  
Thermophilic Archaeon

ABSTRACT A peptidyl prolyl cis-trans isomerase (PPIase) was purified from a thermophilic methanogen, Methanococcus thermolithotrophicus. The PPIase activity was inhibited by FK506 but not by cyclosporine. The molecular mass of the purified enzyme was estimated to be 16 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and 42 kDa by gel filtration. The enzyme was thermostable, with the half-lives of its activity at 90 and 100°C being 90 and 30 min, respectively. The catalytic efficiencies (k cat/Km ) measured at 15°C for the peptidyl substrates,N-succinyl-Ala-Leu-Pro-Phe-p-nitroanilide andN-succinyl-Ala-Ala-Pro-Phe-p-nitroanilide, were 0.35 and 0.20 μM−1 s−1, respectively, in chymotrypsin-coupled assays. The purified enzyme was sensitive to FK506 and therefore was called MTFK (M. thermolithotrophicusFK506-binding protein). The MTFK gene (462 bp) was cloned from anM. thermolithotrophicus genomic library. The comparison of the amino acid sequence of MTFK with those of other FK506-binding PPIases revealed that MTFK has a 13-amino-acid insertion in the N-terminal region that is unique to thermophilic archaea. The relationship between the thermostable nature of MTFK and its structure is discussed.

scholarly journals Characterization of a Thermostable d-Stereospecific Alanine Amidase from Brevibacillus borstelensis BCS-1

2003 ◽  
Vol 69 (2) ◽  
pp. 980-986 ◽  
Author(s):  
Dae Heoun Baek ◽  
Seok-Joon Kwon ◽  
Seung-Pyo Hong ◽  
Mi-Sun Kwak ◽  
Mi-Hwa Lee ◽  
...  
Keyword(s):  
Enzyme Activity ◽  
Amino Acid ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Optimum Temperature ◽  
Gene Encoding ◽  
Ph Range

ABSTRACT A gene encoding a new thermostable d-stereospecific alanine amidase from the thermophile Brevibacillus borstelensis BCS-1 was cloned and sequenced. The molecular mass of the purified enzyme was estimated to be 199 kDa after gel filtration chromatography and about 30 kDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, indicating that the enzyme could be composed of a hexamer with identical subunits. The purified enzyme exhibited strong amidase activity towards d-amino acid-containing aromatic, aliphatic, and branched amino acid amides yet exhibited no enzyme activity towards l-amino acid amides, d-amino acid-containing peptides, and NH2-terminally protected amino acid amides. The optimum temperature and pH for the enzyme activity were 85°C and 9.0, respectively. The enzyme remained stable within a broad pH range from 7.0 to 10.0. The enzyme was inhibited by dithiothreitol, 2-mercaptoethanol, and EDTA yet was strongly activated by Co2+ and Mn2+. The k cat/Km for d-alaninamide was measured as 544.4 ± 5.5 mM−1 min−1 at 50°C with 1 mM Co2+.

scholarly journals Enzyme instability and proteolysis during the purification of an alcohol dehydrogenase from Drosophila melanogaster

1977 ◽  
Vol 163 (2) ◽  
pp. 317-323 ◽  
Author(s):  
D R Thatcher
Keyword(s):  
Drosophila Melanogaster ◽  
Amino Acid ◽  
Alcohol Dehydrogenase ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Evolutionary Significance ◽  
Nitrobenzoic Acid ◽  
A Subunit ◽  
Terminal Amino

The alcohol dehydrogenase of the Drosophila melanogaster adhUF allele (alloenzyme with ultra-fast electrophoretic mobility) was unstable in crude or partially purified preparations. Sodium dodecyl sulphate/polyacrylamide-gel electrophoresis indicated that inactivation was porbably due to proteolytic degradation, and new method of purification of the enzyme was developed. After three steps, namely salmine sulphate precipitation, hydroxyapatite chromatography and Sephadex G-100 gel filtration, a 10-fold purified preparation was obtained. The enzyme produced was relatively stable compared with alcohol dehydrogenase purified by other methods, and was shown to be proteinase-free. The enzyme had a subunit mol.wt. of 24000 and had a single thiol residue per subunit available for titration with 5,5′-dithiobis-(2-nitrobenzoic acid). The amino acid composition and C-terminal amino acid sequence of the enzyme were determined. The substrate specificity of this alcohol dehydrogenase was also characterized. These results are discussed in relation to experiments on the evolutionary significance of thermostability at the adh locus.

scholarly journals Kinetic characterization of yeast alcohol dehydrogenases. Amino acid residue 294 and substrate specificity.

1987 ◽  
Vol 262 (8) ◽  
pp. 3754-3761
Author(s):  
A.J. Ganzhorn ◽  
D.W. Green ◽  
A.D. Hershey ◽  
R.M. Gould ◽  
B.V. Plapp
Keyword(s):  
Amino Acid ◽  
Substrate Specificity ◽  
Amino Acid Residue ◽  
Kinetic Characterization ◽  
Alcohol Dehydrogenases

scholarly journals Streptococcus salivarius Fimbriae Are Composed of a Glycoprotein Containing a Repeated Motif Assembled into a Filamentous Nondissociable Structure

2001 ◽  
Vol 183 (9) ◽  
pp. 2724-2732 ◽  
Author(s):  
Céline Lévesque ◽  
Christian Vadeboncoeur ◽  
Fatiha Chandad ◽  
Michel Frenette
Keyword(s):  
Amino Acid ◽  
Amino Acid Sequence ◽  
Cell Surface ◽  
Polyclonal Antibodies ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Spontaneous Mutant ◽  
Streptococcus Salivarius ◽  
Streptococcal Species ◽  
Repeated Motif

ABSTRACT Streptococcus salivarius, a gram-positive bacterium found in the human oral cavity, expresses flexible peritrichous fimbriae. In this paper, we report purification and partial characterization of S. salivarius fimbriae. Fimbriae were extracted by shearing the cell surface of hyperfimbriated mutant A37 (a spontaneous mutant of S. salivarius ATCC 25975) with glass beads. Preliminary experiments showed that S. salivariusfimbriae did not dissociate when they were incubated at 100°C in the presence of sodium dodecyl sulfate. This characteristic was used to separate them from other cell surface components by successive gel filtration chromatography procedures. Fimbriae with molecular masses ranging from 20 × 106 to 40 × 106Da were purified. Examination of purified fimbriae by electron microscopy revealed the presence of filamentous structures up to 1 μm long and 3 to 4 nm in diameter. Biochemical studies of purified fimbriae and an amino acid sequence analysis of a fimbrial internal peptide revealed that S. salivarius fimbriae were composed of a glycoprotein assembled into a filamentous structure resistant to dissociation. The internal amino acid sequence was composed of a repeated motif of two amino acids alternating with two modified residues: A/X/T-E-Q-M/φ, where X represents a modified amino acid residue and φ represents a blank cycle. Immunolocalization experiments also revealed that the fimbriae were associated with a wheat germ agglutinin-reactive carbohydrate. Immunolabeling experiments with antifimbria polyclonal antibodies showed that antigenically related fimbria-like structures were expressed in two other human oral streptococcal species, Streptococcus mitis andStreptococcus constellatus.

Characterization of an isozyme of S-adenosylmethionine synthetase from rat liver

1984 ◽  
Vol 62 (5) ◽  
pp. 276-279 ◽  
Author(s):  
C. H. Lin ◽  
W. Chung ◽  
K. P. Strickland ◽  
A. J. Hudson
Keyword(s):  
Amino Acids ◽  
Molecular Weight ◽  
Amino Acid ◽  
Enzymatic Synthesis ◽  
Gel Filtration ◽  
Deae Cellulose ◽  
Aromatic Amino Acids ◽  
Adenosylmethionine Synthetase ◽  
Cellulose Column

An isozyme of S-adenosylmethionine synthetase has been purified to homogeneity by ammonium sulfate fractionation, DEAE-cellulose column chromatography, and gel filtration on a Sephadex G-200 column. The purified enzyme is very unstable and has a molecular weight of 120 000 consisting of two identical subunits. Amino acid analysis on the purified enzyme showed glycine, glutamate, and aspartate to be the most abundant and the aromatic amino acids to be the least abundant. It possesses tripolyphosphatase activity which can be stimulated five to six times by S-adenosylmethionine (20–40 μM). The findings support the conclusion that an enzyme-bound tripolyphosphate is an obligatory intermediate in the enzymatic synthesis of S-adenosylmethionine from ATP and methionine.

scholarly journals Biochemical characterization including amino acid and carbohydrate compositions of canine and human brain Thy-1 antigen

1981 ◽  
Vol 197 (3) ◽  
pp. 629-636 ◽  
Author(s):  
J L McKenzie ◽  
A K Allen ◽  
J W Fabre
Keyword(s):  
Monoclonal Antibody ◽  
Amino Acid ◽  
Human Brain ◽  
Affinity Chromatography ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Antibody Affinity ◽  
Lentil Lectin

Human and canine brain Thy-1 antigens were solubilized in deoxycholate and antigen activity was followed both by conventional absorbed anti-brain xenosera of proven specificity and by mouse monoclonal antibodies to canine and human Thy-1. It is shown that greater than 80% of Thy-1 activity in the dog and man binds to lentil lectin, that the mobility on sodium dodecyl sulphate/polyacrylamide-gel electrophoresis of canine and human Thy-1 is identical with that of rat Thy-1 and that the Stokes radius in deoxycholate of canine and human brain Thy-1 is 3.0 nm and 3.25 nm respectively. Both lentil lectin affinity chromatography followed by gel-filtration chromatography on the one hand and monoclonal antibody affinity chromatography on the other gave high degrees of purification of the brain Thy-1 molecule in the dog and man, resulting in single bands staining for both protein and carbohydrate on sodium dodecyl sulphate/polyacrylamide-gel electrophoresis (except for a slight contaminant of higher molecular weight staining for protein but not carbohydrate with human Thy-1 purified by lentil lectin and gel-filtration chromatography). Analysis of canine and human brain Thy-1 purified by monoclonal antibody affinity chromatography with additional gel filtration through Sephadex G-200 showed that these molecules had respectively 38% and 36% carbohydrate. The amino acid and carbohydrate compositions were similar to those previously reported for Thy-1 of the rat and mouse, the main point of interest being the presence in canine and human brain Thy-1 of N-acetylgalactosamine, which has been reported in rat and mouse brain Thy-1 but not in Thy-1 from other tissues.

scholarly journals α-Crystallin. The isolation and characterization of distinct macromolecular fractions

1971 ◽  
Vol 124 (2) ◽  
pp. 337-343 ◽  
Author(s):  
Abraham Spector ◽  
Lu-Ku Li ◽  
Robert C. Augusteyn ◽  
Arthur Schneider ◽  
Thomas Freund
Keyword(s):  
Molecular Weight ◽  
Amino Acid ◽  
Gel Filtration ◽  
Deae Cellulose ◽  
Chemical Difference ◽  
Molecular Weights ◽  
Isolation And Characterization ◽  
Different Populations ◽  
Molecular Weight Fractions

α-Crystallin was isolated from calf lens periphery by chromatography on DEAE-cellulose and gel filtration. Three distinct populations of macromolecules have been isolated with molecular weights in the ranges approx. 6×105−9×105, 0.9×106−4×106and greater than 10×106. The concentration of macromolecules at the molecular-weight limits of a population are very low. The members of the different populations do not appear to be in equilibrium with each other. Further, in those molecular-weight fractions investigated, no equilibrium between members of the same population was observed. The population of lowest molecular weight comprises 65–75% of the total material. The amino acid and subunit composition of the different-sized fractions appear very similar, if not identical. The only chemical difference observed between the fractions is the presence of significant amounts of sugar in the higher-molecular-weight fractions. Subunit molecular weights of approx. 19.5×103and 22.5×103were observed for all α-crystallin fractions.

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 ).

scholarly journals Characterization of Biosynthetic Enzymes for Ectoine as a Compatible Solute in a Moderately Halophilic Eubacterium, Halomonas elongata

1999 ◽  
Vol 181 (1) ◽  
pp. 91-99 ◽  
Author(s):  
Hisayo Ono ◽  
Kazuhisa Sawada ◽  
Nonpanga Khunajakr ◽  
Tao Tao ◽  
Mihoko Yamamoto ◽  
...  
Keyword(s):  
Molecular Mass ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Apparent Molecular Mass ◽  
Optimum Temperature ◽  
Sds Page ◽  
Halomonas Elongata ◽  
Optimum Ph

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.

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