scholarly journals Isolation, Purification, and Characterization of a Polygalacturonase Produced in Penicillium solitum-Decayed ‘Golden Delicious’ Apple Fruit

2009 ◽  
Vol 99 (6) ◽  
pp. 636-641 ◽  
Author(s):  
Wayne M. Jurick ◽  
Ivana Vico ◽  
James L. McEvoy ◽  
Bruce D. Whitaker ◽  
Wojciech Janisiewicz ◽  
...  
Keyword(s):  
Cation Exchange ◽  
Divalent Cations ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Apple Fruit ◽  
Ruthenium Red ◽  
Exchange Chromatography ◽  
Golden Delicious ◽  
Penicillium Solitum

Polygalacturonase (PG) was extracted and purified from decayed ‘Golden Delicious’ apple fruit inoculated with Penicillium solitum. Ammonium sulfate, gel filtration, and cation exchange chromatography were used to purify the enzyme. Both chromatographic methods revealed a single peak corresponding to PG activity. The purified PG most likely originates from the fungus because PG activity from healthy and wounded apple tissue was undetectable. Analysis of cation exchange-purified material using sodium dodecyl sulfate polyacrylamide gel electrophoresis revealed a single 50-kDa band. The enzyme was active over a broad pH range (3 to 7), with optimal activity between pH 4 and 5. PG was highly active at 20 and 37°C but was also detectable at 2, 50, and 75°C. Divalent cations affected PG enzyme activity; Mg and Fe increased, whereas Ca and Mn reduced activity in vitro. Thin-layer chromatographic separation of hydrolysis products and data from a PG plate activity assay based on staining with ruthenium red showed that the enzyme exhibits both exo and endo activity. Purified PG incubated with intact apple fruit tissue in vitro caused a 30% reduction in mass after 48 h, suggesting a role in P. solitum-mediated decay of apple fruit.

scholarly journals The 47-kD fragment of talin is a substrate for protein kinase P

Blood ◽  
1993 ◽  
Vol 82 (11) ◽  
pp. 3343-3349 ◽  
Author(s):  
PC Simons ◽  
L Elias
Keyword(s):  
Protein Kinase ◽  
Ion Exchange ◽  
Sequence Data ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Exchange Chromatography ◽  
Myelogenous Leukemia ◽  
Blue Staining ◽  
Major Protein

Abstract This laboratory has been characterizing protein serine/threonine kinase reactions of hematopoietic tissues, whose most distinguishing characteristics in vitro are stimulation with vesicular phosphatidyl glycerol, and the ability to function using Mn2+ as the sole divalent cation. The major protein substrates are a 73-kD protein and a protein migrating near ovalbumin on sodium dodecyl sulfate polyacrylamide gel electrophoresis. The 47-kD protein was partially purified from cells harvested by leukapheresis from a patient with acute myelogenous leukemia, using ammonium sulfate precipitation and ion exchange chromatography. This partially purified ion-exchange fraction contained an endogenous kinase activity with characteristics similar to those we previously described of protein kinase P (protein kinase, phospholipid- stimulable: PK-P), but not typical of any form of protein kinase C (PK- C). With longer phosphorylation, the 47-kD band showed increasingly lower mobility demonstrable both by Coomassie blue staining and autoradiography, suggesting both that it was multiply phosphorylated, and that the excisable band was pure. The protein was thus eluted from preparative gel slices and digested with endoproteinase lys C. Sequence data from the fragments identified the protein as the 47-kD calpain fragment of talin, a protein found in focal adhesion plaques and some cell-cell contacts. PK-C phosphorylated the 47-kD protein, as has been reported previously, and phosphopeptide mapping disclosed a similar pattern of phosphorylation using either PK-C or the endogenous activity. The 47-kD protein labeled with the endogenous kinase contained predominantly phosphoserine, with some phosphothreonine and a trace of phosphotyrosine. Intact, purified talin was also phosphorylated by PK-P in a phospholipid-stimulable manner, but at 1/20 the rate of the 47-kD fragment.

Effects of Some Vitamins on Lactoperoxidase Enzyme Activity

2009 ◽  
Vol 79 (3) ◽  
pp. 188-194 ◽  
Author(s):  
Melda Sisecioglu ◽  
Murat Cankaya ◽  
Hasan Ozdemir
Keyword(s):  
Ascorbic Acid ◽  
Enzyme Activity ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Bovine Milk ◽  
Exchange Chromatography ◽  
Inhibition Mechanism ◽  
Vitamin K3 ◽  
Vitro Effect

Objective: The present paper investigates the in vitro effect of L-ascorbic acid (vitamin C), menadione sodium bisulfate (vitamin K3), and folic acid on purified lactoperoxidase (LPO). Methods: This enzyme was purified from bovine milk by Amberlite CG 50 resin, CM Sephadex C-50 ion-exchange chromatography, and Sephadex G-100 gel filtration chromatography. Results: Rz (A412/A280) value for the purified LPO was found to be 0.8. Lactoperoxidase was purified 20.45-fold with a yield of 28.8 %. Purity of enzyme was checked by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) method and a single band was observed. All tested vitamins caused inhibition of the enzyme activity and displayed a competitive type of inhibition mechanism. IC50 values of these three vitamins were 2.03 µM, 0.025 mM, and 0.0925 mM, and the Ki constants were 0.508±0.257 µM, 0.0107±0.0044 mM, and 0.0218±0.0019 mM respectively. Conclusion: The vitamins discussed here displayed inhibition-type competition with LPO enzyme at varying concentrations. Our study showed that L-ascorbic acid exhibited a much higher inhibitory effect at lower concentrations, so it was evidently a more potent inhibitor than other vitamins tested.

Stabilization and purification of the secondary metabolism specific enzyme, m-hydroxybenzylalcohol dehydrogenase

1986 ◽  
Vol 32 (2) ◽  
pp. 167-175 ◽  
Author(s):  
Richard E. Scott ◽  
K. S. Lam ◽  
G. M. Gaucher
Keyword(s):  
Secondary Metabolism ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Exchange Chromatography ◽  
Size Exclusion ◽  
Specific Enzyme ◽  
Major Band ◽  
Exclusion Chromatography ◽  
Salt Fractionation

m-Hydroxybenzylalcohol dehydrogenase (EC 1.1.1.97), a secondary metabolism associated protein from stationary phase cultures of Penicillium urticae, was stabilized in crude extracts prior to purification. Stabilization studies resulted in the formulation of an optimal cell breakage and purification buffer. This buffer increased the enzyme's in vitro half-life at 30 °C from 14 to over 800 min which greatly aided purification and enhanced yields. Purification was achieved by salt fractionation, size-exclusion chromatography, affinity chromatography, and ion-exchange chromatography. The 1200-fold purified protein gave only one major band by sodium dodecyl sulphate – polyacrylamide gel electrophoresis.

Influence of divalent cations on rat apolipoprotein transfer to synthetic lipoproteinlike lipid emulsions in vitro

1983 ◽  
Vol 61 (1) ◽  
pp. 63-71 ◽  
Author(s):  
Philip W. Connelly ◽  
Arnis Kuksis
Keyword(s):  
Whole Blood ◽  
Divalent Cations ◽  
Low Density Lipoprotein ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Density Lipoprotein ◽  
Plasma Lipoproteins ◽  
Lipid Emulsions ◽  
Rat Serum

Synthetic lipid emulsions of chylomicron (TG1) and low density lipoprotein (TG2) diameter, consisting of triacylglycerol and phosphatidylcholine, were incubated with rat serum, whole blood, plasma, and postheparin plasma in the presence or absence of divalent cations. The lipid and apoprotein composition of the reisolated Sf > 400 particles was examined by high temperature gas chromatography and sodium dodecyl sulfate – glycerol polyacrylamide gel electrophoresis, respectively. It was found that apoproteins C, E, H, and A-I were associated with TG1 after incubation with whole blood + EDTA, EDTA–plasma, or EDTA–postheparin plasma. Significant amounts of unidentified apoproteins with molecular weights greater than 45 000 were also associated with these particles. Apoprotein E, apoprotein A-I, and a 51 000 dalton apoprotein were associated with the Sf > 400 fraction of TG2 recovered after incubation under the same conditions. The apoprotein profiles were indistinguishable from those previously reported for the corresponding Sf > 400 fraction recovered after intravenous infusion of TG1 and TG2. In the presence of Ca2+ and Mg2+ either in serum or in plasma and postheparin plasma, two additional proteins were recovered in the Sf > 400 fractions of TG1 and TG2. These apoproteins were of molecular weight 28 000 and 48 000 and had not been previously reported as components of plasma lipoproteins.

scholarly journals The 47-kD fragment of talin is a substrate for protein kinase P

Blood ◽  
1993 ◽  
Vol 82 (11) ◽  
pp. 3343-3349
Author(s):  
PC Simons ◽  
L Elias
Keyword(s):  
Protein Kinase ◽  
Ion Exchange ◽  
Sequence Data ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Exchange Chromatography ◽  
Myelogenous Leukemia ◽  
Blue Staining ◽  
Major Protein

This laboratory has been characterizing protein serine/threonine kinase reactions of hematopoietic tissues, whose most distinguishing characteristics in vitro are stimulation with vesicular phosphatidyl glycerol, and the ability to function using Mn2+ as the sole divalent cation. The major protein substrates are a 73-kD protein and a protein migrating near ovalbumin on sodium dodecyl sulfate polyacrylamide gel electrophoresis. The 47-kD protein was partially purified from cells harvested by leukapheresis from a patient with acute myelogenous leukemia, using ammonium sulfate precipitation and ion exchange chromatography. This partially purified ion-exchange fraction contained an endogenous kinase activity with characteristics similar to those we previously described of protein kinase P (protein kinase, phospholipid- stimulable: PK-P), but not typical of any form of protein kinase C (PK- C). With longer phosphorylation, the 47-kD band showed increasingly lower mobility demonstrable both by Coomassie blue staining and autoradiography, suggesting both that it was multiply phosphorylated, and that the excisable band was pure. The protein was thus eluted from preparative gel slices and digested with endoproteinase lys C. Sequence data from the fragments identified the protein as the 47-kD calpain fragment of talin, a protein found in focal adhesion plaques and some cell-cell contacts. PK-C phosphorylated the 47-kD protein, as has been reported previously, and phosphopeptide mapping disclosed a similar pattern of phosphorylation using either PK-C or the endogenous activity. The 47-kD protein labeled with the endogenous kinase contained predominantly phosphoserine, with some phosphothreonine and a trace of phosphotyrosine. Intact, purified talin was also phosphorylated by PK-P in a phospholipid-stimulable manner, but at 1/20 the rate of the 47-kD fragment.

scholarly journals Purification to homogeneity of pig leucocyte catabolin, a protein that causes cartilage resorption in vitro

1983 ◽  
Vol 215 (2) ◽  
pp. 385-392 ◽  
Author(s):  
J Saklatvala ◽  
V A Curry ◽  
S J Sarsfield
Keyword(s):  
Isoelectric Focusing ◽  
Interleukin 1 ◽  
Polyacrylamide Gel Electrophoresis ◽  
Active Material ◽  
Sodium Dodecyl ◽  
Reversed Phase ◽  
Buffy Coat ◽  
Exchange Chromatography ◽  
Nasal Cartilage

Catabolin, a protein that causes proteoglycan resorption in explants of living cartilage, was purified to homogeneity from culture medium conditioned by culturing buffy-coat leucocytes from 60 litres of pig blood in the presence of concanavalin A. The purification steps were (1) gel filtration of concentrated medium, (2) chromatofocusing, (3) hydroxyapatite chromatography, (4) anion-exchange chromatography (Mono Q), (5) reversed-phase high-pressure liquid chromatography (h.p.l.c.) (Zorbax ODS). These achieved approx. 9000-fold purification from the starting material. The purified protein when reduced ran as a single band on sodium dodecyl sulphate (SDS)/polyacrylamide-gel electrophoresis with Mr 21000. On isoelectric focusing its pI was 4.8-5.0, and there was evidence of micro-heterogeneity. The protein co-migrated with active material on h.p.l.c., isoelectric focusing and SDS gels (15 and 12.5% acrylamide) under both reducing and non-reducing conditions. The pure protein caused proteoglycan release from cultured bovine nasal cartilage at 20pM. Its possible identity with interleukin 1 is discussed.

scholarly journals Preliminary characterization of the transcriptional and translational products of the Saccharomyces cerevisiae cell division cycle gene CDC28.

1982 ◽  
Vol 2 (4) ◽  
pp. 412-425 ◽  
Author(s):  
S I Reed ◽  
J Ferguson ◽  
J C Groppe
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
In Vitro Mutagenesis ◽  
Coding Region ◽  
Loop Analysis ◽  
Partial Digestion ◽  
Polyadenylic Acid

The CDC28 gene was subcloned from a plasmid containing a 6.5-kilobase-pair segment of Saccharomyces cerevisiae DNA YRp7(CDC28-3) by partial digestion with Sau3A and insertion of the resulting fragments into the BamHI sites of YRp7 and pRC1. Recombinant plasmids were obtained containing inserts of 4.4 and 3.1 kilobase pairs which were capable of complementing a cdc28(ts) mutation. R-loop analysis indicated that each yeast insert contained two RNA coding regions of about 0.8 and 1.0 kilobase pairs, respectively. In vitro mutagenesis experiments suggested that the smaller coding region corresponded to the CDC28 gene. When cellular polyadenylic acid-containing RNA, separated by agarose gel electrophoresis after denaturation with glyoxal and transferred to nitrocellulose membrane, was reacted with labeled DNA from the smaller coding region, and RNA species of about 1 kilobase in length was detected. Presumably, the discrepancy in size between the R-loop and electrophoretic determinations is due to a segment of polyadenylic acid which is excluded from the R-loops. By using hybridization of the histone H2B mRNAs to an appropriate probe as a previously determined standards, it was possible to estimate the number of CDC28 mRNA copies per haploid cell as between 6 and 12 molecules. Hybrid release translation performed on the CDC29 mRNA directed the synthesis of a polypeptide of 27,000 daltons, as determined by polyacrylamide gel electrophoresis in sodium dodecyl sulfate. This polypeptide was not synthesized when mRNA prepared from a cdc28 nonsense mutant was translated in a parallel fashion. However, if the RNA from a cell containing the CDC28 gene on a plasmid maintained at a high copy number was translated, the amount of in vitro product was amplified fivefold.

C25, an essential RNA polymerase III subunit related to the RNA polymerase II subunit RPB7

1994 ◽  
Vol 14 (9) ◽  
pp. 6164-6170
Author(s):  
P P Sadhale ◽  
N A Woychik
Keyword(s):  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Polyacrylamide Gel Electrophoresis ◽  
Rna Polymerase Iii ◽  
Sodium Dodecyl ◽  
Polymerase Iii ◽  
Conditional Mutant ◽  
5.8S Rrna ◽  
Cell Growth And Viability

We identified a partially sequenced Saccharomyces cerevisiae gene which encodes a protein related to the S. cerevisiae RNA polymerase II subunit, RPB7. Several lines of evidence suggest that this related gene, YKL1, encodes the RNA polymerase III subunit C25. C25, like RPB7, is present in submolar ratios, easily dissociates from the enzyme, is essential for cell growth and viability, but is not required in certain transcription assays in vitro. YKL1 has ABF-1 and PAC upstream sequences often present in RNA polymerase subunit genes. The sodium dodecyl sulfate-polyacrylamide gel electrophoresis mobility of the YKL1 gene product is equivalent to that of the RNA polymerase III subunit C25. Finally, a C25 conditional mutant grown at the nonpermissive temperature synthesizes tRNA at reduced rates relative to 5.8S rRNA, a hallmark of all characterized RNA polymerase III mutants.

scholarly journals Protein phosphatase PP2C in the flagellum of Leishmania major: cloning and characterization

2017 ◽  
Vol 3 ◽  
Author(s):  
A. R. Escalona-Montaño ◽  
R. Pérez-Montfort ◽  
N. Cabrera ◽  
R. Mondragón-Flores ◽  
D. E. Vélez-Ramírez ◽  
...  
Keyword(s):  
Protein Tyrosine Phosphatase ◽  
Protein Phosphatase ◽  
Protein Concentration ◽  
Leishmania Major ◽  
Polyclonal Antibodies ◽  
Divalent Cations ◽  
Tyrosine Phosphatase ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Phosphatase Inhibitors

AbstractThe main goal of this work consisted in cloning, purifying and characterizing a protein phosphatase 2C (PP2C) from promastigotes ofLeishmania major. The gene was cloned and amplified by PCR using specific oligonucleotides and the recombinant protein was purified by affinity chromatography. The peak with maximal protein concentration was analysed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and revealed a protein of 44·9 kDa with PP2C activity. This activity was dependent on divalent cations (Mg+2and Mn+2) and was optimal at pH of 8·5, using phosphothreonine as the substrate. Sanguinarine inhibited the activity of the recombinantLmPP2C, while protein tyrosine phosphatase inhibitors had no effect. The recombinantLmPP2C was used to generate polyclonal antibodies. These antibodies recognized a protein of 44·9 kDa in differentLeishmaniaspecies; theLmPP2C was localized in the flagellar pocket and the flagellum of promastigotes.

scholarly journals Phosphorylation of synaptic-membrane proteins from ox cerebral cortex in vitro. Preparation of fractions enriched in phosphorylated proteins by using extraction with detergents and urea, and gel filtration

1977 ◽  
Vol 163 (2) ◽  
pp. 369-378 ◽  
Author(s):  
P R Dunkley ◽  
H Holmes ◽  
R Rodnight
Keyword(s):  
Cerebral Cortex ◽  
Cyclic Amp ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Polyacrylamide Gel ◽  
Synaptic Membrane ◽  
Hydroxyl Groups ◽  
Phosphorylated Proteins

Synaptic-membrane fragments from ox cerebral cortex contain basal and cyclic AMP-stimulated protein kinase(s) that transfer 32P from [gamma-32P]ATP to hydroxyl groups of serine and threonine residues in membrane-protein substrates. In the present work, labelled membrane fragments were partitioned into soluble and insoluble fractions with Triton X-100, Nonidet P. 40, sodium deoxycholate and urea, and the distribution of 32P-labelled protein in the fractions was determined by polyacrylamide-gel electrophoresis and radioautography. A high percentage of phosphorylated protein sustrates remained insoluble, including those whose phosphorylation was most highly stimulated by cyclic AMP. Whole membrane fragments and samples prepared by detergent extraction were fractionated on Sepharose 6B columns in the presence of low concentrations of sodium dodecyl sulphate and pooled fractions were analysed by polyacrylamide-gel electrophoresis and radioautography. Phosphorylated proteins were fractionated on the basis of their molecular weight, but homogeneous protein was not obtained. The results are discussed in relation to the techniques used and the results obtained in other laboratories.

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