scholarly journals VARIATION OF MUTAGENIC ACTION ON NONSENSE MUTANTS AT DIFFERENT SITES IN THE ISO-1-CYTOCHROME c GENE OF YEAST

Genetics ◽  
1974 ◽  
Vol 78 (1) ◽  
pp. 97-113
Author(s):  
Fred Sherman ◽  
John W Stewart
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Cytochrome C ◽  
Base Pair ◽  
Nitrous Acid ◽  
Nucleotide Sequences ◽  
Mutagenic Action ◽  
Base Pairs ◽  
Wide Range ◽  
Cytochromes C

ABSTRACT Three ochre and two amber mutants in yeast have been definitively identified by the amino acid replacements in iso-1-cytochromes c from intragenic revertants. Except for rare and sometimes unusual changes, all of the replacements were single amino acids whose codons differed from UAA or UAG by one base. These assignments, which were based on the absence of tryptophan replacements in ochre revertants, could be corroborated from the studies of two groups of suppressors that were shown to act on either the ochre or amber mutants. All five nonsense mutants are located at different sites in the cyc1 gene and all are at sites that can be occupied by amino acids having a wide range of structures. The relative frequencies of the amino acid replacements indicate that identical codons located at different sites may respond differently to a mutagenic agent. Notably glutamine replacements occurred almost exclusively in UV-induced revertants of only one ochre mutant cyc1-9, but not at all or at reduced proportions in the others. Similarly, lysine replacements occurred almost exclusively in the NA-induced revertants of only the ochre mutant cyc1-72, but not at all in the others. These and other results reveal that mutation of A·T base pairs by UV and nitrous acid are dependent upon the location of the codon within the gene as well as the location of the base pair within the codon. From these findings, it appears as if the type of base-pair changes induced by UV and nitrous acid are strongly influenced by adjacent nucleotide sequences.

scholarly journals The amino acid sequence of cytochromes c-551 from three species of Pseudomonas

1973 ◽  
Vol 131 (3) ◽  
pp. 485-498 ◽  
Author(s):  
R. P. Ambler ◽  
Margaret Wynn
Keyword(s):  
Amino Acids ◽  
Pseudomonas Aeruginosa ◽  
Amino Acid ◽  
Cytochrome C ◽  
Amino Acid Sequence ◽  
Amino Acid Sequences ◽  
Mitochondrial Cytochrome ◽  
Cytochromes C ◽  
Lending Library ◽  
Single Peptide

The amino acid sequences of the cytochromes c-551 from three species of Pseudomonas have been determined. Each resembles the protein from Pseudomonas strain P6009 (now known to be Pseudomonas aeruginosa, not Pseudomonas fluorescens) in containing 82 amino acids in a single peptide chain, with a haem group covalently attached to cysteine residues 12 and 15. In all four sequences 43 residues are identical. Although by bacteriological criteria the organisms are closely related, the differences between pairs of sequences range from 22% to 39%. These values should be compared with the differences in the sequence of mitochondrial cytochrome c between mammals and amphibians (about 18%) or between mammals and insects (about 33%). Detailed evidence for the amino acid sequences of the proteins has been deposited as Supplementary Publication SUP 50015 at the National Lending Library for Science and Technology, Boston Spa, Yorks. LS23 7BQ, U.K., from whom copies can be obtained on the terms indicated in Biochem. J. (1973), 131, 5.

scholarly journals Analysis of Htra Gene from Zebrafish (Danio Rerio)

2015 ◽  
Vol 10 (2) ◽  
Author(s):  
M. Murwantoko ◽  
Chio Oka ◽  
Masashi Kawaichi
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Amino Acid Sequence ◽  
Danio Rerio ◽  
Serine Proteases ◽  
Catalytic Domain ◽  
Fruit Fly ◽  
Wide Range ◽  
Igf Binding ◽  
Bacterial Homolog

HtrA which is characterized by the combination of a trypsin-like catalytic domain with at least one C-terminalPDZ domain is a highly conserved family of serine proteases found in a wide range of organisms. However theidentified HtrA family numbers varies among spesies, for example the number of mammalian, Eschericia coli,fruit fly-HtrA family are 4, 3 and 1 gene respectively. One gene is predicted exist in zebrafish. Since no completeinformation available on zebrafish HtrA, in this paper zebrafish HtrA (zHtrA) gene was analyzed. The zHtrA isbelonged to HtrA1 member and predicted encodes 478 amino acids with a signal peptide, a IGF binding domain,a Kazal-type inhibitor domain in the up stream of HtrA-bacterial homolog. At the amino acid sequence the zHtrA1showed the 69%, 69%, 68%, 54% and 54% with the rat HtrA1, mouse HtrA1, human HtrA1, human HtrA3 andmouse HtrA4 respectively. The zHtrA1 is firstly expressed at 60 hpf and mainly in the vertebral rudiments in thetail region.

An Automated Detection System for Most L-α-Amino Acids

1969 ◽  
Vol 15 (2) ◽  
pp. 154-161 ◽  
Author(s):  
K Van Dyke ◽  
C Szustkiewicz
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Detection System ◽  
Automated System ◽  
Acid Oxidase ◽  
Enzymatic Reactions ◽  
Amino Acid Oxidase ◽  
Automated Method ◽  
Wide Range

Abstract An automated system for the determination of the L-α form of the majority of amino acids is presented. The method is based upon oxidative deamination of the amino acid coupled with oxidation of o-dianisidine by hydrogen peroxide. This procedure can be used comparatively for the determination of a mixture of L-α-amino acids or for the majority of separated L-α-amino acids (especially in conjunction with column separations from urine and blood which give falsely positive identification with ninhydrin detection). The stereospecific nature of the L-α-amino acid oxidase enables the investigator to quantitate the amount of L-α-amino acid in the presence of the D-α form. From an academic viewpoint, the extreme sensitivity and wide range of the detection system make it advantageous for the study of the enzyme itself. This automated method also may be employed to follow enzymatic reactions—e.g., those catalyzed by peptidases or racemases. The methodology is extremely convenient with good reagent stability and is much more sensitive than manometric technics.

The Synthesis of a Cubane-Substituted Dipeptide

2012 ◽  
Vol 65 (6) ◽  
pp. 690 ◽  
Author(s):  
Quentin I. Churches ◽  
Roger J. Mulder ◽  
Jonathan M. White ◽  
John Tsanaktsidis ◽  
Peter J. Duggan
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
High Sensitivity ◽  
Pure Form ◽  
Bioactive Molecules ◽  
Side Chains ◽  
Cyclic Hydrocarbon ◽  
Wide Range ◽  
Effective Synthesis ◽  
Dipeptide Derivative

Amino acids and peptides bearing cyclic hydrocarbon side-chains are of interest in the development of a wide range of bioactive molecules. The preparation of an amino acid and a dipeptide derivative bearing an unfunctionalised cubane substituent is described. Attempts to prepare a cubylalanine derivative via the corresponding dehydroalanine were unsuccessful due to the high sensitivity of this vinyl cubane compound. Conversely, the addition of cubyllithium to a (RS)-glyoxylate sulfinimine led to an effective synthesis of a cubylglycine derivative and a cubane-substituted dipeptide in diastereomerically pure form.

scholarly journals The amino acid sequence of cytochrome c of Fagopyrum esculentum Moench (buckwheat) and Brassica oleracea L. (cauliflower)

1971 ◽  
Vol 124 (4) ◽  
pp. 783-785 ◽  
Author(s):  
E. W. Thompson ◽  
M. Richardson ◽  
D. Boulter
Keyword(s):  
Amino Acid ◽  
Cytochrome C ◽  
Amino Acid Sequence ◽  
Brassica Oleracea ◽  
Amino Acid Sequences ◽  
Cytochromes C ◽  
Lending Library ◽  
Fagopyrum Esculentum Moench ◽  
Mitochondrial Cytochromes ◽  
Brassica Oleracea L

The amino acid sequences of buckwheat and cauliflower cytochromes c were determined on 1½μmol and 1μmol of protein respectively. The molecules consist of 111 residues and are homologous with other plant mitochondrial cytochromes c. Experimental details are given in a supplementary paper that has been deposited as Supplementary Publication SUP 50005 at the National Lending Library for Science and Technology, Boston Spa, Yorks. LS23 7BQ, U.K., from whom copies can be obtained on the terms indicated in Biochem. J. (1971), 121, 7.

The relationships between the concentrations of individual amino acids and protein in wheat and barley grain grown at selected locations throughout Manitoba

1996 ◽  
Vol 76 (2) ◽  
pp. 163-169 ◽  
Author(s):  
R. J. Boila ◽  
S. C. Stothers ◽  
L. D. Campbell
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Barley Grain ◽  
Regression Equations ◽  
Acid Protein ◽  
Wide Range ◽  
Indispensable Amino Acids ◽  
Protein Amino Acids ◽  
Barley Protein ◽  
Amino Acid Concentrations

The concentrations of protein and individual amino acids were determined in the grain from three cultivars of wheat and three cultivars of barley, each grown at 12 locations throughout Manitoba over 3 consecutive years. Protein concentration differed (P < 0.05) among the cultivars of wheat but not (P > 0.05) among cultivars of barley. Although the concentrations of several amino acids differed (P < 0.05) among cultivars of wheat or barley the differences among cultivars of each grain were not considered to be critical in relation to the requirements for indispensable amino acids for swine or poultry. The percentage of an ammo acid in the DM of wheat and barley increased (P < 0.05) linearly with an increase in percentage of protein in the grain. The wide range of r2 (0.29 to 0.88) obtained for this amino acid-protein relationship may be due to the different effect of environment (location and year of growth) on the concentration of individual amino acids, compared to protein, among cultivars of wheat or barley. The percentage of total variance due to an interaction between cultivar and environment was low for protein but was several fold higher for individual amino acids. The error in the prediction of amino acid concentrations with regression equations may be no different than the error associated with predicting the mean concentrations of amino acids in the protein of wheat or barley as g (100 g protein)−1, and obtained from tabulations of analyses. However, regression equations for lysine in wheat and barley did account for the significant (P < 0.05) decrease in concentration of lysine in the protein as the percentage of protein in these grains increased. Key words: Grain, wheat, barley, protein, amino acids, Manitoba

Use-dependent block of excitatory amino acid currents in cultured neurons by ketamine

1987 ◽  
Vol 58 (2) ◽  
pp. 251-266 ◽  
Author(s):  
J. F. MacDonald ◽  
Z. Miljkovic ◽  
P. Pennefather
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Aspartic Acid ◽  
Excitatory Amino Acids ◽  
Hippocampal Neurons ◽  
Excitatory Amino Acid ◽  
Outward Current ◽  
Bathing Solution ◽  
Wide Range ◽  
Repeated Applications

1. Mouse hippocampal neurons grown in dissociated cell culture were patch clamped using a whole cell voltage clamp (discontinuous switching clamp) technique. The currents generated by pressure applications of excitatory amino acids were studied over a wide range of holding potentials, and current-voltage curves were plotted. Excitatory amino acids that activated the N-methyl-D-aspartic acid (NMDA) receptor demonstrated some degree of desensitization with repeated applications, whereas the currents observed in response to kainic acid (KAI) did not. Desensitization could be minimized by keeping the frequency of application sufficiently low (i.e., less than 0.1 Hz). 2. The short-acting dissociative anaesthetic, ketamine (2–50 microM), selectively blocked L-aspartic acid (L-Asp), NMDA, and L-glutamic acid (L-Glu) currents while sparing those in response to KAI. Therefore, ketamine is a relatively selective blocker of the NMDA response versus that (those) activated by KAI. 3. The block by ketamine of excitatory amino acid currents is highly voltage dependent. Concentrations of ketamine that had little effect on outward current responses at depolarized potentials were quite effective at blocking inward current responses at hyperpolarized potentials. In contrast, DL-2-amino-5-phosphonovaleric acid (APV) was equally effective at blocking both inward and outward currents (voltage independent). The voltage dependence of ketamine (a positively charged molecule) could be accounted for if ketamine blocked the NMDA response by binding to a site that experienced 55% of the membrane field. 4. In the presence of ketamine, peak inward currents evoked by repeated applications of NMDA, L-Asp, or L-Glu progressively declined to a steady-state level of block (use-dependent block). This decrement occurred at frequencies much lower than those that were employed to demonstrate desensitization (in the absence of ketamine). Moving the membrane potential to depolarized values did not, in itself, relieve the ketamine block. However, if the appropriate excitatory amino acid (L-Asp, NMDA, L-Glu) was applied during the period of depolarization, a relief of the block could be demonstrated. No recovery from the blockade occurred with periods of rest (no amino acid application) as long as 5 min. Furthermore, no recovery was observed even when ketamine was washed out of the bathing solution until the appropriate agonist was applied. Thus recovery from blockade, like development of blockade, was use dependent.(ABSTRACT TRUNCATED AT 400 WORDS)

scholarly journals Increased thermal stability of proteins in the presence of amino acids

1994 ◽  
Vol 303 (1) ◽  
pp. 147-153 ◽  
Author(s):  
S Taneja ◽  
F Ahmad
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Cytochrome C ◽  
Thermal Denaturation ◽  
Thermal Transition ◽  
Native Protein ◽  
Guanidinium Chloride ◽  
Isoleucine Leucine ◽  
Hydrophobic Amino Acids ◽  
Thermal Stability Of

This study is a systematic attempt to understand the roles of osmolytes in protecting proteins against denaturing stress. Thermal denaturation of cytochrome c has been studied in the presence of various concentrations of all L-amino acids that are more hydrophobic than glycine and have a solubility of 0.1 M or higher in water at 25 degrees C. The basic observations are as follows. (1) Arginine and histidine destabilize the native protein; both Tm (the midpoint of thermal transition) and delta GDH2O (25 degrees C) (the Gibbs energy of stabilization) decrease with increasing amino acid concentration. (2) Isoleucine, leucine and phenylalanine have no effect on Tm and deltaGDH2O (25 degrees C). (3) Valine and less hydrophobic amino acids stabilize the protein in terms of Tm but deltaGDH2O (25 degrees C) is unchanged. This observation was confirmed by the study of isothermal denaturation of cytochrome c by guanidinium chloride which suggested that delta GDH2O is independent of osmolyte concentration, but Cm (the midpoint of transition) is increased in their presence. (4) In the case of stabilizers, change in Tm/mol of amino acid decreases with increasing hydrophobicity of these osmolytes.

A Study of Relations between the Absorption of Amino Acids, Dipeptides, Water and Electrolytes in the Normal Human Jejunum

1975 ◽  
Vol 49 (5) ◽  
pp. 401-408 ◽  
Author(s):  
D. B. A. Silk ◽  
P. D. Fairclough ◽  
Nicola J. Park ◽  
Annette E. Lane ◽  
Joan P. W. Webb ◽  
...  
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Sodium Chloride ◽  
Human Subjects ◽  
Sodium Content ◽  
Sodium Chloride Solutions ◽  
Electrolyte Absorption ◽  
Wide Range ◽  
Osmotic Solution ◽  
Normal Human

1. A double-lumen perfusion technique was used to study the effect of a wide range of concentrations of the dipeptide glycyl-l-alanine and its constituent amino acids on water and electrolyte absorption from iso-osmotic solutions in the upper jejunum of normal human subjects. 2. There was no significant absorption of water and electrolytes from sodium chloride solution (150 mmol/l) but the presence of the dipeptide or its constituent amino acids stimulated water and electrolyte absorption. 3. Water absorption reached a peak at increasing amino acid and dipeptide concentrations and then tailed off. Our data suggest that the tailing off is not solely due to the diminished sodium content of the solutions. 4. During perfusion of the dipeptide-sodium chloride and amino acid-sodium chloride solutions solute and water were absorbed as an iso-osmotic solution. Analysis of the results indicates that this could occur at high dipeptide concentrations only if the majority of the dipeptide enters the cell intact.

scholarly journals The amino acid sequence of cytochrome c from Spinacea oleracea L. (spinach)

1973 ◽  
Vol 131 (2) ◽  
pp. 253-256 ◽  
Author(s):  
R. H. Brown ◽  
M. Richardson ◽  
R. Scogin ◽  
D. Boulter
Keyword(s):  
Amino Acid ◽  
Cytochrome C ◽  
Amino Acid Sequence ◽  
Science And Technology ◽  
Spinacea Oleracea ◽  
Cytochromes C ◽  
Lending Library ◽  
Mitochondrial Cytochromes

The amino acid sequence of spinach (Spinacea oleracea L., var. Monster Viroflay) cytochrome c was determined on 1μmol of protein. The molecule consists of 111 residues and is homologous with other mitochondrial cytochromes c. Experimental details are given in a supplementary paper that has been deposited as Supplementary Publication SUP 50013, at the National Lending Library for Science and Technology, Boston Spa, Yorks. LS23 7BQ, U.K., from whom copies can be obtained on the terms indicated in Biochem. J. (1973), 131, 5.

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