scholarly journals Two globin strains in the giant annelid extracellular haemoglobins

1987 ◽  
Vol 241 (2) ◽  
pp. 441-445 ◽  
Author(s):  
T Gotoh ◽  
F Shishikura ◽  
J W Snow ◽  
K I Ereifej ◽  
S N Vinogradov ◽  
...  
Keyword(s):  
Amino Acid ◽  
Lumbricus Terrestris ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Amino Acid Sequences ◽  
Amino Acid Residues ◽  
Terminal Amino Acid ◽  
Reverse Phase ◽  
Terminal Amino ◽  
Polypeptide Chains

The constituent polypeptide chains I, II, III and IV of the giant extracellular haemoglobin of the oligochaete Lumbricus terrestris were isolated by mono Q ion-exchange chromatography and C8 reverse-phase chromatography. The N-terminal amino acid sequences of Lumbricus chains I, III and IV were determined and aligned with those of Lumbricus chain II and the four chains of the extracellular haemoglobin of the polychaete Tylorrhynchus heterochaetus. Three invariant amino acid residues, Cys-7, Val-15 and Trp-19, were found to occur in the N-terminal segments (17-22 residues) of the eight chains of Lumbricus and Tylorrhynchus haemoglobins. In addition, it was found that the eight sequences could be separated into two groups: ‘A’, consisting of Lumbricus chains I and II and Tylorrhynchus chains I and IIA, having invariant Lys-14 and Lys-16, and ‘B’, consisting of Lumbricus chains III and IV and Tylorrhynchus IIB and IIC, having invariant Cys-6, Ser-8 and Asp-11. This result suggests that there are two strains of globin chain in the annelid extracellular haemoglobins.

The Enzymic Digestion of Cod Tropomyosin

1962 ◽  
Vol 19 (6) ◽  
pp. 1095-1104
Author(s):  
B. Truscott ◽  
P. L. Hoogland ◽  
P. H. Odense ◽  
A. E. Waddell
Keyword(s):  
Amino Acid ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Performic Acid ◽  
Amino Acid Residues ◽  
Amino Groups ◽  
Terminal Amino Acid ◽  
Enzymic Digestion ◽  
Disulphide Bonds ◽  
Terminal Amino

Tropomyosin from cod muscle can be oxidized with performic acid to cleave disulphide bonds without degradation of other amino acid residues. The ε-amino groups of lysine within the molecule can be substituted readily with carbobenzoxy-groups for protection against digestion by trypsin. The digestions by trypsin of carbobenzoxy-substituted tropomyosin, and by chymotrypsin of oxidized tropomyosin, have been shown to be reproducible, providing peptides suitable for amino acid sequence studies. The peptides so obtained were separated by ion-exchange chromatography using a Beckman/Spinco Amino Acid Analyzer.After treatment with urea, cod tropomyosin does not yield a free N-terminal amino acid as has been reported for rabbit tropomyosin.

scholarly journals Isolation of four forms of acetone-induced cytochrome P-450 in chicken liver by h.p.l.c. and their enzymic characterization

1990 ◽  
Vol 269 (1) ◽  
pp. 85-91 ◽  
Author(s):  
J F Sinclair ◽  
S Wood ◽  
L Lambrecht ◽  
N Gorman ◽  
L Mende-Mueller ◽  
...  
Keyword(s):  
Amino Acid ◽  
Amino Acid Sequence ◽  
Exchange Chromatography ◽  
Amino Acid Sequences ◽  
Chicken Liver ◽  
Terminal Amino Acid ◽  
Catalytic Activities ◽  
Terminal Amino ◽  
Cytochrome P 450 ◽  
Terminal Amino Acid Sequence

The purpose of this study was to purify and characterize the forms of cytochrome P-450 induced in chicken liver by acetone or ethanol. Using high performance liquid ion-exchange chromatography, we were able to isolate at least four different forms of cytochrome P-450 which were induced by acetone in chicken liver. All four forms of cytochrome P-450 proved to be distinct proteins, as indicated by their N-terminal amino acid sequences and their reconstituted catalytic activities. Two of these forms, also induced by glutethimide in chicken embryo liver, appeared to be cytochromes P450IIH1 and P450IIH2. Both of these cytochromes P-450 have identical catalytic activities towards benzphetamine demethylation. However, they differ in their abilities to hydroxylate p-nitrophenol and to convert acetaminophen into a metabolite that forms a covalent adduct with glutathione at the 3-position. Another form of cytochrome P-450 induced by acetone is highly active in the hydroxylation of p-nitrophenol and in the conversion of acetaminophen to a reactive metabolite, similar to reactions catalysed by mammalian cytochrome P450IIE. Yet the N-terminal amino acid sequence of this form has only 30-33% similarity with cytochrome P450IIE purified from rat, rabbit and human livers. A fourth form of cytochrome P-450 was identified whose N-terminal amino acid sequence and enzymic activities do not correspond to any mammalian cytochromes P-450 reported to be induced by acetone or ethanol.

Thermolytic digest of chicken pepsin

1981 ◽  
Vol 46 (8) ◽  
pp. 1994-2004 ◽  
Author(s):  
Miroslav Baudyš ◽  
Vladimír Kostka ◽  
Helena Keilová
Keyword(s):  
Amino Acid ◽  
Amino Acid Sequence ◽  
Linear Structure ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Terminal Amino Acid ◽  
Terminal Amino ◽  
Terminal Amino Acid Sequence ◽  
High Voltage Electrophoresis ◽  
Final Purification

Chicken pepsin prepared by the activation of pepsinogen was digested with thermolysin. The thermolytic digest was fractionated by chromatography on Sephadex G-25 fine. Certain fractions were subsequently subjected to ion exchange chromatography on Dowex 50-X2. The final purification was effected by paper chromatography and high voltage electrophoresis. By these procedures a series of homogeneous peptides was obtained; of the latter 54 nonoverlapping (save for a few exceptions) peptides are described in this paper. These peptides in addition to the thermolytic peptides reported before represent 80% of the linear structure of the whole molecule. The N-terminal amino acid sequence of chicken pepsin is discussed from the viewpoint of the recent data obtained by the analysis of the thermolytic digest.

THE USE OF REGION SPECIFIC RADIOIMMUNOASSAYS FOR CHARACTERIZATION OF CIRCULATING CALCITONIN IN PATIENTS WITH MEDULLARY CARCINOMA OF THE THYROID GLAND

1979 ◽  
Vol 91 (3) ◽  
pp. 449-461 ◽  
Author(s):  
Lisbeth Myhre ◽  
Kaare M. Gautvik
Keyword(s):  
Amino Acid ◽  
Amino Acid Sequences ◽  
Molecular Forms ◽  
Amino Acid Residues ◽  
Terminal Amino Acid ◽  
Amino Terminal ◽  
Terminal Fragment ◽  
Terminal Amino ◽  
Carboxy Terminal ◽  
Amino Terminal Fragment

ABSTRACT Two antisera with known region specificities have been used to characterize calcitonin immunoreactivity (iCT) in serum of patients with medullary thyroid carcinoma (MCT). Antiserum I which was raised against the synthetic hormone (1–32 amino acid residues), contained heterogeneous populations of immunoglobulins directed predominantly against carboxyterminal sequences of the hormone, but the antiserum reacted also with the amino-terminal fragment (1–10 amino acid residues). Antiserum II, which was raised against the carboxy-terminal hormone fragment (11–32 amino acid residues) reached equally well with the intact hormone and the C-terminal fragment, but showed negligible binding of the amino terminal fragment. Antiserum I measured therefore both amino-terminal and carboxy-terminal sequences of calcitonin while antiserum II measured only carboxy-terminal amino acid sequences. In 40 patients with MCT, antiserum I measured usually the highest concentration of serum iCT suggesting the presence of non-uniform hormone immunoreactivity. The different molecular forms of circulating iCT in 7 MCT patients were explored by using antiserum I after gel filtration on Sephadex G-100. The patients who were selected on basis of iCT measurement in serum using antiserum I and II, could be divided into 3 groups which showed characteristic iCT profiles. Group 1, in which antiserum II measured a higher concentration of serum iCT, contained predominantly (60–70 %) small fragments of calcitonin immunoreactivity. On the other hand, in the sera of group 3 in which antisera I measured an equal or the highest concentrations, the dominant form of the hormone consisted of molecular sequences equal to or larger than the intact hormone (90 %). In group 2, the two antisera measured an equal amount of serum iCT and molecular forms consisting mostly of larger hormone fragments dominated (50 %). All the patients were normocalcaemic in spite of frequently grossly elevated serum iCT, and 33 out of 36 patients had normal serum immunoreactive parathyroid hormone. In conclusion: 1. Serum iCT is heterogeneous and represents peptides of quite different molecular size with no or low biological activity. 2. Most of the serum calcitonin immunoreactivity consists of peptides with carboxy-terminal amino acid sequences. 3. Most, if not all, of the amino-terminal calcitonin immunoreactivity is due to monomeric and polymeric hormonal forms.

scholarly journals Deletion of the Actin-Associated Tropomyosin Tpm3 Leads to Reduced Cell Complexity in Cultured Hippocampal Neurons—New Insights into the Role of the C-Terminal Region of Tpm3.1

Cells ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 715
Author(s):  
Tamara Tomanić ◽  
Claire Martin ◽  
Holly Stefen ◽  
Esmeralda Parić ◽  
Peter Gunning ◽  
...  
Keyword(s):  
Amino Acid ◽  
Hippocampal Neurons ◽  
Molecular Mechanisms ◽  
Growth Cones ◽  
Amino Acid Residues ◽  
Terminal Amino Acid ◽  
C Terminus ◽  
Primary Mouse ◽  
Terminal Amino

Tropomyosins (Tpms) have been described as master regulators of actin, with Tpm3 products shown to be involved in early developmental processes, and the Tpm3 isoform Tpm3.1 controlling changes in the size of neuronal growth cones and neurite growth. Here, we used primary mouse hippocampal neurons of C57/Bl6 wild type and Bl6Tpm3flox transgenic mice to carry out morphometric analyses in response to the absence of Tpm3 products, as well as to investigate the effect of C-terminal truncation on the ability of Tpm3.1 to modulate neuronal morphogenesis. We found that the knock-out of Tpm3 leads to decreased neurite length and complexity, and that the deletion of two amino acid residues at the C-terminus of Tpm3.1 leads to more detrimental changes in neurite morphology than the deletion of six amino acid residues. We also found that Tpm3.1 that lacks the 6 C-terminal amino acid residues does not associate with stress fibres, does not segregate to the tips of neurites, and does not impact the amount of the filamentous actin pool at the axonal growth cones, as opposed to Tpm3.1, which lacks the two C-terminal amino acid residues. Our study provides further insight into the role of both Tpm3 products and the C-terminus of Tpm3.1, and it forms the basis for future studies that aim to identify the molecular mechanisms underlying Tpm3.1 targeting to different subcellular compartments.

scholarly journals Factor D̄ of the alternative pathway of human complement. Purification, alignment and N-terminal amino acid sequences of the major cyanogen bromide fragments, and localization of the serine residue at the active site

1980 ◽  
Vol 187 (3) ◽  
pp. 863-874 ◽  
Author(s):  
D M Johnson ◽  
J Gagnon ◽  
K B Reid
Keyword(s):  
Amino Acid ◽  
Sequence Analysis ◽  
Amino Acid Sequence ◽  
Alternative Pathway ◽  
Amino Acid Sequences ◽  
Serine Residue ◽  
Amino Acid Sequence Analysis ◽  
Terminal Amino Acid ◽  
Terminal Amino ◽  
Terminal Amino Acid Sequence

The serine esterase factor D of the complement system was purified from outdated human plasma with a yield of 20% of the initial haemolytic activity found in serum. This represented an approx. 60 000-fold purification. The final product was homogeneous as judged by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis (with an apparent mol.wt. of 24 000), its migration as a single component in a variety of fractionation procedures based on size and charge, and its N-terminal amino-acid-sequence analysis. The N-terminal amino acid sequence of the first 36 residues of the intact molecule was found to be homologous with the N-terminal amino acid sequences of the catalytic chains of other serine esterases. Factor D showed an especially strong homology (greater than 60% identity) with rat ‘group-specific protease’ [Woodbury, Katunuma, Kobayashi, Titani, & Neurath (1978) Biochemistry 17, 811-819] over the first 16 amino acid residues. This similarity is of interest since it is considered that both enzymes may be synthesized in their active, rather than zymogen, forms. The three major CNBr fragments of factor D, which had apparent mol.wts. of 15 800, 6600 and 1700, were purified and then aligned by N-terminal amino acid sequence analysis and amino acid analysis. By using factor D labelled with di-[1,3-14C]isopropylphosphofluoridate it was shown that the CNBr fragment of apparent mol.wt. 6600, which is located in the C-terminal region of factor D, contained the active serine residue. The amino acid sequence around this residue was determined.

Importance of Terminal Amino Acid Residues to the Transport of Oligopeptides across the Caco-2 Cell Monolayer

2017 ◽  
Vol 65 (35) ◽  
pp. 7705-7712 ◽  
Author(s):  
Long Ding ◽  
Liying Wang ◽  
Zhipeng Yu ◽  
Sitong Ma ◽  
Zhiyang Du ◽  
...  
Keyword(s):  
Amino Acid ◽  
Cell Monolayer ◽  
Amino Acid Residues ◽  
Terminal Amino Acid ◽  
Terminal Amino
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