Comparison of plasma membrane FABP and mitochondrial isoform of aspartate aminotransferase from rat liver

1993 ◽  
Vol 265 (5) ◽  
pp. G894-G902 ◽  
Author(s):  
D. D. Stump ◽  
S. L. Zhou ◽  
P. D. Berk
Keyword(s):  
Plasma Membrane ◽  
Fatty Acid ◽  
Amino Acid ◽  
Rat Liver ◽  
Aspartate Aminotransferase ◽  
High Performance ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Fatty Acid Binding ◽  
Sds Page

A relationship between plasma membrane fatty acid binding protein (FABPpm), a putative membrane transporter for long-chain fatty acids, and the mitochondrial isoform of aspartate aminotransferase (m-AspAT) has been reported. Accordingly, we have compared the chemical and immunological properties of rat liver m-AspAT with those of rat liver FABPpm isolated by two procedures: 1) detergent solubilization of the membranes followed by purification via fatty acid affinity chromatography (FABP-1) or 2) salt extraction of the membranes and subsequent purification by high-performance liquid chromatography (HPLC; FABP-2). Comparison of the three protein preparations revealed no differences with respect to NH2-terminal amino acid sequence, amino acid composition, peptides from tryptic digests, AspAT enzymatic activity, isoelectric point, mobility on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), retention on five different HPLC columns, and immunoprecipitation and immunoblotting of SDS-PAGE separated proteins with polyclonal antisera. Examination of the proteins by nondenaturing PAGE showed a consistent second band in FABP-1 and FABP-2 not always present in m-AspAT. However, whenever present, this band was immunoreactive with antibodies to both m-AspAT and FABP-1. Hence, FABP-1 and FABP-2 are indistinguishable from one another. They are also at least closely related, if not identical, to m-AspAT.

Study on Degradation of Radix Isatidis Polypeptide in Artificial Gastrointestinal Environment

2014 ◽  
Vol 989-994 ◽  
pp. 1020-1024
Author(s):  
Nan Nan ◽  
Xi Jing Liu
Keyword(s):  
Gel Electrophoresis ◽  
Free Amino ◽  
High Performance ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Radix Isatidis ◽  
Sds Page ◽  
Electrophoresis Method ◽  
Amino Acid Levels ◽  
Different Molecular Weight

Radix Isatidis is a traditional Chinese medicine for treatment of influenza and inflammation in China. In this paper, in order to study the degradation situation of Radix Isatidis polypeptide in artificial gastrointestinal environment, the SDS-PAGE (Sodium dodecyl sulfate-polyacrylamide gel electrophoresis) method was used to detect the degradation of Radix Isatidis polypeptide in artificial intestinal juice and gastric juice, and it showed that Radix Isatidis peptides could be degradated to different degrees. HPLC (High Performance Liquid Chromatography) was used to determine the change of peptides degradation, and it indicated that free amino acid levels did not change significantly. The result after degradation was also detected by BCA method, and it showed that there were still a large number of polypeptides in the liquid. From this experiment we can come to this conclusion that Radix Isatidis polypeptides in artificial gastrointestinal juice mostly degraded into a series of different molecular weight peptides.

scholarly journals Heterologous Expression and Characterization of A Novel Ochratoxin A Degrading Enzyme, N-acyl-L-amino Acid Amidohydrolase, from Alcaligenes faecalis

Toxins ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 518
Author(s):  
Honghai Zhang ◽  
Yunpeng Zhang ◽  
Tie Yin ◽  
Jing Wang ◽  
Xiaolin Zhang
Keyword(s):  
Amino Acid ◽  
Ochratoxin A ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Alcaligenes Faecalis ◽  
Degrading Enzyme ◽  
Sds Page ◽  
Ochratoxin Α ◽  
Acid Amidohydrolase

Ochratoxin A (OTA) is a well-known, natural contaminant in foods and feeds because of its toxic effects, such as nephrotoxicity in various animals. Recent studies have revealed that Alcaligenes faecalis could generate enzymes to efficiently degrade OTA to ochratoxin α (OTα) in vitro. In an effort to obtain the OTA degrading mechanism, we purified and identified a novel degrading enzyme, N-acyl-L-amino acid amidohydrolase (AfOTase), from A. faecalis DSM 16503 via mass spectrometry. The same gene of the enzyme was also encountered in other A. faecalis strains. AfOTase belongs to peptidase family M20 and contains metal ions at the active site. In this study, recombination AfOTase was expressed and characterized in Escherichia coli. The molecular mass of recombinant rAfOTase was approximately 47.0 kDa, as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The enzyme exhibited a wide temperature range (30–70 °C) and pH adaptation (4.5–9.0) and the optimal temperature and pH were 50 °C and 6.5, respectively.

scholarly journals Extraction, Characterization and Antioxidant Activity in vitro of Proteins from Semen Allii Fistulosi

Molecules ◽  
2018 ◽  
Vol 23 (12) ◽  
pp. 3235
Author(s):  
Min Zuo ◽  
Xiao-xiao Liu ◽  
Di Liu ◽  
Hang-yun Zhao ◽  
Lu-lu Xuan ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
High Performance ◽  
Orthogonal Design ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Reducing Power ◽  
Raw Material ◽  
Extraction Solvent ◽  
Sds Page

Semen Allii Fistulosi (PSAF) is the seed of Allium fistulosum L. of the Liliaceae family. The purpose of this study was to extract, characterize, and evaluate the antioxidant activity in vitro of proteins. Using single factor and orthogonal design, the optimum conditions of extraction were determined to be as follows: extraction time 150 min, pH 8.5, temperature 60 °C, and ratio (v/w, mL/g) of extraction solvent to raw material 35. The isoelectric point of the pH was determined to be about 4.4 and 10.2, by measuring the protein content of PSAF solutions at different pH values. The amino acid composition of PSAF was determined by high performance liquid chromatography (HPLC), and the results suggested that the species of amino acids contained in the PSAF was complete. Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS–PAGE) analysis showed the molecular weight was mainly between 40 and 55 kDa, and Fourier-transform infrared spectroscopy (FTIR) characterized prevalent protein absorption peaks. PSAF exhibited potent scavenging activities against DPPH assays, via targeting of hydroxyl and superoxide radicals, while chelating Fe2+ activity and demonstrating weak reducing power. This work revealed that PSAF possessed potential antioxidant activity in vitro, suggesting potential for use of PSAF as a natural antioxidant.

scholarly journals Antithrombin III Budapest: a single amino acid substitution (429Pro to Leu) in a region highly conserved in the serpin family

Blood ◽  
1992 ◽  
Vol 79 (5) ◽  
pp. 1206-1212 ◽  
Author(s):  
RJ Olds ◽  
DA Lane ◽  
R Caso ◽  
M Panico ◽  
HR Morris ◽  
...  
Keyword(s):  
Amino Acid ◽  
Amino Acid Substitution ◽  
Antithrombin Iii ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Single Amino Acid Substitution ◽  
Single Amino Acid ◽  
Sds Page ◽  
Additional Support ◽  
Variant Protein

Abstract Antithrombin III (AT) is a major plasma serine protease inhibitor and a member of the serpin family of proteins. We have characterized the molecular and genetic basis of AT Budapest, an inherited variant of AT that is associated with thrombotic disease in affected family members. A single amino acid substitution, 429Pro to Leu, was identified, occurring in a region of the molecule that is highly conserved in members of the serpin family. Two forms of variant protein were present in approximately equal amounts in the plasma of the propositus, who is homozygous for the mutation. One form, which had apparently normal Mr, bound heparin strongly and retained some residual thrombin inhibitory activity. The other form had only weak heparin affinity and no antiproteinase activity, and had slightly decreased mobility on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) under nonreducing conditions; this normalized in the presence of a reducing agent, suggesting it was caused by a change in conformation. Additional support for a difference in conformation of the two forms of variant was provided by the finding that the fraction that bound heparin- Sepharose was recognized by a monoclonal antibody raised against normal AT, whereas the weak-affinity fraction was not.

scholarly journals Cloning and expression of two human p70 S6 kinase polypeptides differing only at their amino termini.

1991 ◽  
Vol 11 (11) ◽  
pp. 5541-5550 ◽  
Author(s):  
J R Grove ◽  
P Banerjee ◽  
A Balasubramanyam ◽  
P J Coffer ◽  
D J Price ◽  
...  
Keyword(s):  
Rat Liver ◽  
Kinase Activity ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Cloning And Expression ◽  
S6 Kinase ◽  
P70 S6 Kinase ◽  
Cos Cells ◽  
Sds Page

Two classes of human cDNA encoding the insulin/mitogen-activated p70 S6 kinase have been isolated; the two classes differ only in the 5' region, such that the longer polypeptide (p70 S6 kinase alpha I; calculated Mr 58,946) consists of 525 amino acids, of which the last 502 residues are identical in sequence to the entire polypeptides encoded by the second cDNA (p70 S6 kinase alpha II; calculated Mr 56,153). Both p70 S6 kinase polypeptides predicted by these cDNAs are present in p70 S6 kinase purified from rat liver, and each is thus expressed in vivo. Moreover, both polypeptides are expressed from a single mRNA transcribed from the (longer) p70 S6 kinase alpha I cDNA through the utilization of different translational start sites. Although the two p70 S6 kinase polypeptides differ by only 23 amino acid residues, the slightly longer alpha I polypeptide exhibits anomalously slow mobility on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), migrating at an apparent Mr of 90,000 probably because of the presence of six consecutive Arg residues immediately following the initiator methionine. Transient expression of p70 alpha I and alpha II S6 kinase cDNA in COS cells results in a 2.5- to 4-fold increase in overall S6 kinase activity. Upon immunoblotting, the recombinant p70 polypeptides appear as a closely spaced ladder of four to five bands between 65 and 70 kDa (alpha II) and 85 and 90 kDa (alpha I). Transfection with the alpha II cDNA yields only the smaller set of bands, while transfection with the alpha I cDNA generates both sets of bands. Mutation of Met-24 in the alpha I cDNA to Leu or Thr suppresses synthesis of the alpha II polypeptides. Only the p70 alpha I and alpha II polypeptides of slowest mobility on SDS-PAGE comigrate with the 70- and 90-kDa proteins observed in purified rat liver S6 kinase. Moreover, it is the recombinant p70 polypeptides of slowest mobility that coelute with S6 kinase activity on anion-exchange chromatography. The slower mobility and higher enzymatic activity of these p70 proteins is due to Ser/Thr phosphorylation, inasmuch as treatment with phosphatase 2A inactivates kinase activity and increases the mobility of the bands on SDS-PAGE in an okadaic acid-sensitive manner. Thus, the recombinant p70 S6 kinase undergoes multiple phosphorylation and partial activation in COS cells. Acquisition of S6 protein kinase catalytic function, however, is apparently restricted to the most extensively phosphorylated recombinant polypeptides.

Purification and characterization of the extracellular α-amylase activity of the yeast Schwanniomyces alluvius

1987 ◽  
Vol 65 (10) ◽  
pp. 899-908 ◽  
Author(s):  
F. Moranelli ◽  
M. Yaguchi ◽  
G. B. Calleja ◽  
A. Nasim
Keyword(s):  
Amino Acid ◽  
Amylase Activity ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Deae Cellulose ◽  
Exchange Chromatography ◽  
Proteinase K ◽  
Ph Optimum ◽  
Sds Page

The extracellular α-amylase activity of the yeast Schwanniomyces alluvius has been purified by anion-exchange chromatography on DEAE-cellulose and gel-filtration chromatography on Sephadex G-100. Sodium dodecyl sulfate – polyacrylamide gel electrophoresis (SDS–PAGE) and N-terminal amino acid analysis of the purified sample indicated that the enzyme preparation was homogeneous. The enzyme is a glycoprotein having a molecular mass of 52 kilodaltons (kDa) estimated by SDS–PAGE and 39 kDa by gel filtration on Sephadex G-100. Chromatofocusing shows that it is an acidic protein. It is resistant to trypsin but sensitive to proteinase K. Its activity is inhibited by the divalent cation chelators EDTA and EGTA and it is insensitive to sulfhydryl-blocking agents. Exogenous divalent cations are inhibitory as are high concentrations of monovalent salts. The enzyme has a pH optimum between 3.75 and 5.5 and displays maximum stability in the pH range of 4.0–7.0. Under the conditions tested, the activity is maximal between 45 and 50 °C and is very thermolabile. Analysis of its amino acid composition supports its acidic nature.

scholarly journals Antithrombin III Budapest: a single amino acid substitution (429Pro to Leu) in a region highly conserved in the serpin family

Blood ◽  
1992 ◽  
Vol 79 (5) ◽  
pp. 1206-1212 ◽  
Author(s):  
RJ Olds ◽  
DA Lane ◽  
R Caso ◽  
M Panico ◽  
HR Morris ◽  
...  
Keyword(s):  
Amino Acid ◽  
Amino Acid Substitution ◽  
Antithrombin Iii ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Single Amino Acid Substitution ◽  
Single Amino Acid ◽  
Sds Page ◽  
Additional Support ◽  
Variant Protein

Antithrombin III (AT) is a major plasma serine protease inhibitor and a member of the serpin family of proteins. We have characterized the molecular and genetic basis of AT Budapest, an inherited variant of AT that is associated with thrombotic disease in affected family members. A single amino acid substitution, 429Pro to Leu, was identified, occurring in a region of the molecule that is highly conserved in members of the serpin family. Two forms of variant protein were present in approximately equal amounts in the plasma of the propositus, who is homozygous for the mutation. One form, which had apparently normal Mr, bound heparin strongly and retained some residual thrombin inhibitory activity. The other form had only weak heparin affinity and no antiproteinase activity, and had slightly decreased mobility on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) under nonreducing conditions; this normalized in the presence of a reducing agent, suggesting it was caused by a change in conformation. Additional support for a difference in conformation of the two forms of variant was provided by the finding that the fraction that bound heparin- Sepharose was recognized by a monoclonal antibody raised against normal AT, whereas the weak-affinity fraction was not.

Cloning and expression of two human p70 S6 kinase polypeptides differing only at their amino termini

1991 ◽  
Vol 11 (11) ◽  
pp. 5541-5550
Author(s):  
J R Grove ◽  
P Banerjee ◽  
A Balasubramanyam ◽  
P J Coffer ◽  
D J Price ◽  
...  
Keyword(s):  
Rat Liver ◽  
Kinase Activity ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Cloning And Expression ◽  
S6 Kinase ◽  
P70 S6 Kinase ◽  
Cos Cells ◽  
Sds Page

Two classes of human cDNA encoding the insulin/mitogen-activated p70 S6 kinase have been isolated; the two classes differ only in the 5' region, such that the longer polypeptide (p70 S6 kinase alpha I; calculated Mr 58,946) consists of 525 amino acids, of which the last 502 residues are identical in sequence to the entire polypeptides encoded by the second cDNA (p70 S6 kinase alpha II; calculated Mr 56,153). Both p70 S6 kinase polypeptides predicted by these cDNAs are present in p70 S6 kinase purified from rat liver, and each is thus expressed in vivo. Moreover, both polypeptides are expressed from a single mRNA transcribed from the (longer) p70 S6 kinase alpha I cDNA through the utilization of different translational start sites. Although the two p70 S6 kinase polypeptides differ by only 23 amino acid residues, the slightly longer alpha I polypeptide exhibits anomalously slow mobility on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), migrating at an apparent Mr of 90,000 probably because of the presence of six consecutive Arg residues immediately following the initiator methionine. Transient expression of p70 alpha I and alpha II S6 kinase cDNA in COS cells results in a 2.5- to 4-fold increase in overall S6 kinase activity. Upon immunoblotting, the recombinant p70 polypeptides appear as a closely spaced ladder of four to five bands between 65 and 70 kDa (alpha II) and 85 and 90 kDa (alpha I). Transfection with the alpha II cDNA yields only the smaller set of bands, while transfection with the alpha I cDNA generates both sets of bands. Mutation of Met-24 in the alpha I cDNA to Leu or Thr suppresses synthesis of the alpha II polypeptides. Only the p70 alpha I and alpha II polypeptides of slowest mobility on SDS-PAGE comigrate with the 70- and 90-kDa proteins observed in purified rat liver S6 kinase. Moreover, it is the recombinant p70 polypeptides of slowest mobility that coelute with S6 kinase activity on anion-exchange chromatography. The slower mobility and higher enzymatic activity of these p70 proteins is due to Ser/Thr phosphorylation, inasmuch as treatment with phosphatase 2A inactivates kinase activity and increases the mobility of the bands on SDS-PAGE in an okadaic acid-sensitive manner. Thus, the recombinant p70 S6 kinase undergoes multiple phosphorylation and partial activation in COS cells. Acquisition of S6 protein kinase catalytic function, however, is apparently restricted to the most extensively phosphorylated recombinant polypeptides.

scholarly journals Studies on fatty acid-binding proteins. The diurnal variation shown by rat liver fatty acid-binding protein

1987 ◽  
Vol 242 (3) ◽  
pp. 913-917 ◽  
Author(s):  
T C I Wilkinson ◽  
D C Wilton
Keyword(s):  
Fatty Acid ◽  
Rat Liver ◽  
Fatty Acid Binding Protein ◽  
Binding Protein ◽  
Polyacrylamide Gel Electrophoresis ◽  
Small Variation ◽  
Fatty Acid Binding Proteins ◽  
Peroxisome Proliferator ◽  
Fatty Acid Binding ◽  
Acid Binding Protein

The concentration of fatty acid-binding protein in rat liver was examined by SDS/polyacrylamide-gel electrophoresis, by Western blotting and by quantifying the fluorescence enhancement achieved on the binding of the fluorescent probe 11-(dansylamino)undecanoic acid. A 2-3-fold increase in the concentration of this protein produced by treatment of rats with the peroxisome proliferator tiadenol was readily detected; however, only a small variation in the concentration of the protein due to a diurnal rhythm was observed. This result contradicts the 7-10-fold variation previously reported for this protein [Hargis, Olson, Clarke & Dempsey (1986) J. Biol. Chem. 261, 1988-1991].

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