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F Bossa

Publications and source records attributed to F Bossa.

At least 91 records · Page 5Linked to original sources
PubMed1989

Amino acid sequence of alpha-chain of hemoglobin IV from trout (Salmo irideus).

The amino acid sequence of the alpha-chain of trout hemoglobin (Hb) IV is given, thus completing the primary structure of the hemoglobin component of trout's blood characterized by the Root effect. The trout Hb IV alpha-chain consists of 142 amino acid residues; comparison with the corresponding sequences from human and carp hemoglobins shows differences of 50.0 and 35.9%, respectively. A difference of 39.6% is found with the alpha-chain of trout Hb I, the other major hemoglobin component of trout blood, devoid of heterotropic effects.

Amino Acid Sequence↗
PubMed1989

Stoichiometry and stability of the adduct formed between human 4-aminobutyrate aminotransferase and 4-aminohex-5-enoate: sequence of a labelled peptide.

The reaction between human 4-aminobutyrate aminotransferase and the anti-epileptic drug 4-aminohex-5-enoate, an irreversible inhibitor of the enzyme, has been studied using the radiolabelled compound. The inactivated enzyme was found to lose radiolabel over a period of a few days at 37 degrees C but even in the presence of the coenzyme, pyridoxal phosphate, no enzyme activity returned. At 4 degrees C the radiolabelled inhibitor remained stably bound. The amount of enzyme-bound 4-aminohex-5-enoate was significantly less than would be expected if one mol of inhibitor was bound per mol of active site. Reversed phase chromatography of a tryptic digest of the labelled enzyme showed that, apart from material eluting at the front of the chromatogram, all of the radioactivity was in a single fraction. This fraction contained a peptide, the sequence of which indicated that it included the lysine that binds the coenzyme and that the major release of radioactivity occurred in an Edman degradation cycle corresponding to this residue.

4-Aminobutyrate Transaminase↗
PubMed1988

Aprotinin-like isoinhibitors in bovine organs.

Previous studies have shown that bovine spleen contains, besides aprotinin (bovine pancreatic trypsin inhibitor, BPTI), three iso-inhibitors (I-III), which are structurally and functionally very similar to BPTI. The primary structure of inhibitors I and II indicates that they are not post-translational products of BPTI, in agreement with independent findings on two homologous genes reported to be present in the bovine genome, which encode BPTI and inhibitors I and II, respectively. A careful reinvestigation on the occurrence of these inhibitors in various bovine organs is presented in this paper, based on their isolation with standard biochemical techniques and on functional and structural studies. All data indicate that the same isoinhibitors found in spleen are also present, besides BPTI, in organs such as lung, liver and pituitary gland, where they were never found before. BPTI and inhibitor II always prevail.

Amino Acid Sequence↗
PubMed1987

Primary structure of a protease isoinhibitor from bovine spleen. A possible intermediate in the processing of the primary gene product.

Sequence studies on the protease isoinhibitor I isolated from bovine spleen have revealed that it consists of two molecular variants which differ only in the presence of an additional COOH-terminal residue, asparagine, in the less abundant form. The complete amino acid sequence shows that they are composed of 65 or 66 residues and predicts Mr of 7223 or 7338, respectively. The sequences correspond exactly to the 58-residue polypeptide chain of spleen isoinhibitor II plus NH2- and COOH-terminal extensions of 2 and 5 or 6 amino acid residues, respectively. Moreover the entire sequences are located within the 100-residue structure deduced from the mRNA and DNA sequences of the putative precursor. These data support the idea that the molecular variants of isoinhibitor I are either mature proteins with distinct functional roles, or intermediates in the multistage processing of the primary product of gene expression, which eventually leads to the mature protein, i.e. inhibitor II.

Amino Acid Sequence↗
PubMed1987

The primary structure of iron superoxide dismutase from Escherichia coli.

The complete amino acid sequence of iron superoxide from Escherichia coli has been determined. The sequence was deduced from analysis of peptides obtained after cleavage of the carboxymethylated apoenzyme with trypsin. Stapholococcus aureus protease or CNBr. The polypeptide chain is made up of 192 residues and is easily aligned with the other known amino acid sequences of iron and manganese superoxide dismutases from various sources. The iron superoxide dismutase from E. coli shows a significantly higher homology with the iron enzyme from a different organism than with the manganese isoenzyme from E. coli.

Amino Acid Sequence↗
PubMed1987

The primary structure of rabbit liver cytosolic serine hydroxymethyltransferase.

The complete amino acid sequence of cytosolic serine hydroxymethyltransferase from rabbit liver was determined. The sequence was determined from analysis of peptides isolated from tryptic and cyanogen bromide cleavages of the enzyme. Special procedures were used to isolate and sequence the C-terminal and blocked N-terminal peptides. Each of the four identical subunits of the enzyme consists of 483 residues. The sequence could be easily aligned with the sequence of Escherichia coli serine hydroxymethyltransferase. The primary structural homology between the rabbit and E. coli enzymes is about 42%. The importance of the primary and predicted secondary structural homology between the two enzymes is discussed.

Amino Acid Sequence↗
PubMed1987

The primary structure of iron-superoxide dismutase from Photobacterium leiognathi.

The complete amino acid sequence of iron-superoxide dismutase from Photobacterium leiognathi was determined. The sequence was deduced following characterization of the peptides obtained from tryptic, chymotryptic, and Staphylococcus aureus V-8 protease digests of the apoprotein. The amino acid sequence listed below is made up of 193 residues. It is the first complete sequence to be determined for an iron-superoxide dismutase. The iron-superoxide dismutase shows the same order of homology with the manganese-superoxide dismutases as these enzymes show among themselves. No homology was observed with the copper/zinc-containing class of superoxide dismutases. Ala-Phe-Glu-Leu-Pro-Ala-Leu-Pro-Phe-Ala-Met-Asn-Ala-Leu-Glu-Pro-His-Ile- Ser-Gln-Glu-Thr-Leu-Glu-Tyr-His-Tyr-Gly-Lys-His-His-Asn-Thr-Tyr-Val-Val- Lys-Leu-Asn-Gly-Leu-Val-Glu-Gly-Thr-Glu-Leu-Ala-Glu-Lys-Ser-Leu-Glu-Glu- Ile-Ile-Lys-Thr-Ser-Thr-Gly-Gly-Val-Phe-Asn-Asn-Ala-Ala-Gln-Val-Trp-Asn- His-Thr-Phe-Tyr-Trp-Asn-Cys-Leu-Ala-Pro-Asn-Ala-Gly-Gly-Glu-Pro-Thr-Gly- Glu-Val-Ala-Ala-Ala-Ile-Glu-Lys-Ala-Phe-Gly-Ser-Phe-Ala-Glu-Phe-Lys-Ala- Lys-Phe-Thr-Asp-Ser-Ala-Ile-Asn-Asn-Phe-Gly-Ser-Ser-Trp-Thr-Trp-Leu-Val- Lys-Asn-Ala-Asn-Gly-Ser-Leu-Ala-Ile-Val-Asn-Thr-Ser-Asn-Ala-Gly-Cys-Pro- Ile-Thr-Glu-Glu-Gly-Val-Thr-Pro-Leu-Leu-Thr-Val-Asp-Leu-Trp-Glu-His-Ala- Tyr-Tyr-Ile-Asp-Tyr-Arg-Asn-Leu-Arg-Pro-Ser-Tyr-Met-Asp-Gly-Phe-Trp-Ala- Leu-Val-Asn-Trp-Asp-Phe-Val-Ser-Lys-Asn-Leu-Ala-Ala.

Amino Acid Sequence↗
PubMed1987

A simple microcomputer program for predicting the secondary structure of proteins.

An Applesoft BASIC program is presented which applies the Chou-Fasman and Garnier-Osguthorpe-Robson rules for predicting the secondary structure of proteins. This program plots the result of predictions and shows the charge distribution and the consensus prediction. The program is run on an Apple IIe and the results are printed by an Imagewriter printer.

Computers↗
PubMed1987

PROTEUS: a suite of programs for prediction of structural features of proteins using an Apple IIe.

We have implemented several algorithms, developed by various authors for predicting structural features of proteins from their primary structure, on an Apple IIe and collected them in a suite, named PROTEUS. This suite incorporates: (i) methods for predicting secondary structure; (ii) the algorithm for computing the hydropathy profile using one out of five available sets of parameters; (iii) the algorithms for calculating the hydrophobic moment plot; and (iv) for performing the amphipathic analysis using one out of four available sets of parameters. The suite has a utility program for storing on a disk the sequence to be analysed. As an example, we applied some of the methods included in PROTEUS to predict the structure of a mitochondrial leader peptide. The results suggest the occurrence of structural features possibly related to the import of proteins into mitochondria.

Algorithms↗
PubMed1986

Serine hydroxymethyltransferase. Effect of proteases on the activity and structure of the cytosolic enzyme.

Homogeneous preparations of cytosolic serine hydroxymethyltransferase from rabbit liver were incubated with several different proteases. Chymotrypsin rapidly cleaves a tetradecapeptide from the NH2-terminal end of the enzyme with the enzyme retaining full catalytic activity. Trypsin digestion results in the release of several small peptides from the NH2-terminal end of the enzyme. The remaining core protein is reduced in molecular mass by about 3500 Da. With L-serine as substrate the core protein has 1.5 times the activity of the native enzyme. The difference in activity is due to a change in Vmax since the Km values for L-serine and tetrahydrofolate are unchanged. When allothreonine is used as the substrate the activity of the trypsin-treated enzyme is unchanged. Ks values for glycine and several folate compounds are also unchanged for the trypsin-digested enzyme. The relative distribution of three glycine-enzyme complexes shows only small differences between the native and trypsin-digested enzyme. Thermal denaturation studies show that the trypsin-digested enzyme has a thermal transition three degrees lower than the native enzyme but the same enthalpy of denaturation. These results suggest that the 25-30 amino acid residues from the NH2-terminal end of the enzyme are not important in determining the catalytic activity and structural stability of the purified enzyme. Several other proteases had no observable effect on the activity and size of the enzyme. All of the proteases tested inactivated the apoenzyme and digested it into small fragments. The loss of enzyme activity in frozen liver is probably the result of the enzyme slowly being converted to the apoenzyme form, which is susceptible to protease degradation.

Animals↗
PubMed1986

Primary structure of a cationic Cu,Zn superoxide dismutase. The sheep enzyme.

The complete amino acid sequence of Cu,Zn superoxide dismutase from sheep erythrocytes has been determined. The sequence is very similar to that of the bovine enzyme, having the same number of residues (151) and only two substitutions in the 'hypervariable' region (residues 17-30). The 5 overall substitutions confer a positive charge on the sheep enzyme at neutral pH (pI approximately equal to 8). This charge is localized outside the active site region. The catalytic efficiency of the sheep enzyme is 15% less than that of the cow enzyme, confirming the hypothesis that the enzyme activity is related to the concentration of positive surface charge near the active site channel.

Amino Acid Sequence↗
PubMed1986

The primary structure of ornithine aminotransferase. Identification of active-site sequence and site of post-translational proteolysis.

Tentative assignments of functional residues in rat liver mitochondrial ornithine aminotransferase have recently been made using the amino acid sequence deduced from a cDNA clone [(1985) J.Biol.Chem. 260, 12993-12997]. Partial sequences obtained using the pure mature protein demonstrate that one of these assignments, that of Lys 292 as the residue that binds the coenzyme pyridoxal phosphate, is correct. However, the identification of the Glu 34-Gln 35 bond as the site of post-translational proteolysis is in error. This cleavage occurs instead at Ala 25-Thr 26.

Amino Acid Sequence↗
PubMed1986

The complete amino acid sequences of cytosolic and mitochondrial aspartate aminotransferases from horse heart, and inferences on evolution of the isoenzymes.

We report here the complete amino acid sequences of the cytosolic and mitochondrial aspartate aminotransferases from horse heart. The two sequences can be aligned so that 48.1% of the amino acid residues are identical. The sequences have been compared with those of the cytosolic isoenzymes from pig and chicken, the mitochondrial isoenzymes from pig, chicken, rat, and human, and the enzyme from Escherichia coli. The results suggest that the mammalian cytosolic and mitochondrial isoenzymes have evolved at equal and constant rates whereas the isoenzymes from chicken may have evolved somewhat more slowly. Based on the rate of evolution of the mammalian isoenzymes, the gene-duplication event that gave rise to cytosolic and mitochondrial aspartate aminotransferases is estimated to have occurred at least 10(9) years ago. The cytosolic and mitochondrial isoenzymes are equally related to the enzyme from E. coli; the prokaryotic and eukaryotic enzymes diverged from one another at least 1.3 X 10(9) years ago.

Amino Acid Sequence↗
PubMed1985

The primary structure of mitochondrial aspartate aminotransferase from human heart.

The complete amino acid sequence of the mitochondrial aspartate aminotransferase (L-aspartate:2-oxoglutarate aminotransferase, EC 2.6.1.1) from human heart has been determined based mainly on analysis of peptides obtained by digestion with trypsin and by chemical cleavage with cyanogen bromide. Comparison of the sequence with those of the isotopic isoenzymes from pig, rat and chicken showed 27, 29 and 55 differences, respectively, out of a total of 401 amino acid residues. Evidence for structural microheterogeneity at position 317 has also been obtained.

Amino Acid Sequence↗
PubMed1985

Primary structure and antiproteolytic activity of a Kunitz-type inhibitor from bovine spleen.

The amino acid sequence of protease inhibitor II, previously isolated from bovine spleen, has been completely elucidated and reveals a high homology (approximately 90%) with that of bovine pancreatic trypsin inhibitor (BPTI), the well-known Kunitz inhibitor. The secondary and tertiary structure of this new inhibitor appears similar to that of BPTI. Whereas its affinity for bovine trypsin, chymotrypsin, and trypsinogen is almost identical to that of BPTI, the affinity for porcine pancreatic kallikrein is decreased, as expected on the basis of the amino acid substitutions. Analysis of the pH dependence of the affinity constant confirms the previous assignment of the ionizable groups, whose pK values are perturbed on complex formation, to kallikrein and not to the inhibitor molecule.

Amino Acid Sequence↗
PubMed1985

Primary structure of porcine Cu,Zn superoxide dismutase.

The complete amino acid sequence of Cu,Zn superoxide dismutase from porcine erythrocytes has been determined. Comparison of the sequence with that of the bovine enzyme shows an overall high degree of homology with conservation of the crucial residues and the presence of two regions prone to variation. In one of these hypervariable regions the insertion of one residue with respect to the bovine enzyme and evidence of structural microheterogeneity has been observed. On the basis of the three-dimensional structure of the bovine enzyme no obvious relationship is apparent between a specific amino acid replacement and the unique pH-dependence pattern of the activity of the porcine enzyme.

Amino Acid Sequence↗