Reaction of metallic nitrilotriacetates with histamine

1969 ◽  
Vol 47 (8) ◽  
pp. 1269-1273 ◽  
Author(s):  
A. L. Beauchamp ◽  
J. Israeli ◽  
H. Saulnier
Keyword(s):  
Potentiometric Titration ◽  
Formation Constants ◽  
Amino Group ◽  
Mixed Complex ◽  
Ph Values ◽  
Titration Curves ◽  
Terminal Amino ◽  
Complex Ion

Cu(II), Ni(II), Co(II), and Zn(II) nitrilotriacetates (MeX−) react with histamine nitrate (LH+) to form a protonated mixed complex MeXLH where the metal appears to be bound only to the tertiary imidazolic nitrogen of histaminium ion. At higher pH values the proton dissociates to yield a mixed complex ion MeXL− in which both the imidazolic nitrogen and the terminal amino group are coordinated. The formation constants of these species were calculated from the potentiometric titration curves.

CONDITIONAL FORMATION CONSTANTS FOR ALUMINUM-ORGANIC MATTER COMPLEXES

1982 ◽  
Vol 62 (4) ◽  
pp. 571-575 ◽  
Author(s):  
W. L. HARGROVE ◽  
G. W. THOMAS
Keyword(s):  
Organic Matter ◽  
Complex Formation ◽  
Strong Dependence ◽  
Formation Constants ◽  
Batch Method ◽  
Potentiometric Titrations ◽  
Ph Values ◽  
Titration Curves ◽  
Al Adsorption

The objective of this study was to determine conditional formation constants which are dependent on pH for Al-organic matter complexes. Potentiometric titrations of H-organic matter in the presence of 0, 0.004 and 0.01 M AlCl3 were carried out by the batch method. The conditional formation constants were calculated by simply relating the amount of complex formed to the amounts of unreacted metal and ligand. The addition of Al3+ resulted in displacement of the titration curves, indicating complex formation. The formation constants (log K′f) increased as the pH increased, illustrating the strong dependence of Al adsorption on pH. Values for log K′f ranged from 1.78 to 3.90 in this study.

Synthesis of three Salmonella epitopes for biosensor studies of carbohydrate–antibody interactions

2002 ◽  
Vol 80 (8) ◽  
pp. 1131-1140 ◽  
Author(s):  
Henry N Yu ◽  
Chang-Chun Ling ◽  
David R Bundle
Keyword(s):  
Key Words ◽  
Self Assembled Monolayers ◽  
Antigenic Determinants ◽  
Amino Group ◽  
Assembled Monolayers ◽  
Construction Of Self ◽  
Terminal Amino ◽  
Salmonella Serotypes ◽  
O Antigens ◽  
Antibody Interactions

Disaccharides 1-3 corresponding to the antigenic determinants of Salmonella serotypes A, B, and D1 were synthesized in a form suited for use in biosensors. The disaccharide determinants each contain a unique 3,6-dideoxyhexose, namely abequose (3,6-dideoxy-D-xylo-hexose), paratose (3,6-dideoxy-D-ribohexose), and tyvelose (3,6-dideoxy-D-arabino-hexose), are α-linked to the 3-position of D-mannopyranose. The disaccharides were further derivatized with a linear aglycon that has a terminal amino group, and can be readily coupled to pertinent chains carrying a terminal thiol for the construction of self-assembled monolayers (SAMs). Efficient routes that employed a single 3,6-dideoxygenation step were developed for the synthesis of paratoside 15 and tyveloside 22.Key words: Salmonella O-antigens, lipopolysaccharide, abequose, paratose, tyvelose, 3,6-dideoxyhexose, deoxygenation, glycoside tethers, immobilization via pentenyl glycosides.

Purification and partial amino acid sequence of thuricin S, a new anti-Listeriabacteriocin from Bacillus thuringiensis

2007 ◽  
Vol 53 (2) ◽  
pp. 284-290 ◽  
Author(s):  
Sonia Chehimi ◽  
François Delalande ◽  
Sophie Sablé ◽  
Mohamed-Rabeh Hajlaoui ◽  
Alain Van Dorsselaer ◽  
...  
Keyword(s):  
Bacillus Thuringiensis ◽  
Proteinase K ◽  
Terminal Sequence ◽  
Partial Amino Acid Sequence ◽  
Ph Values ◽  
Heat Stable ◽  
Isolation And Characterization ◽  
Terminal Amino ◽  
Edman Sequencing

We report the isolation and characterization of a new bacteriocin, thuricin S, produced by the Bacillus thuringiensis subsp. entomocidus HD198 strain. This antibacterial activity is sensitive to proteinase K, is heat-stable, and is stable at a variety of pH values (3–10.5). The monoisotopic mass of thuricin S purified by high perfomance liquid chromatography, as determined with mass spectrometry ESI-TOF-MS, is 3137.61 Da. Edman sequencing and NanoESI-MS/MS experiments provided the sequence of the 18 N-terminal amino acids. Interestingly, thuricin S has the same N-terminal sequence (DWTXWSXL) as bacthuricin F4 and thuricin 17, produced by B. thuringiensis strains BUPM4 and NEB17, respectively, and could therefore be classified as a new subclass IId bacteriocin.

scholarly journals Assessment of Two Theoretical Methods to Estimate Potentiometric Titration Curves of Peptides:  Comparison with Experiment

2006 ◽  
Vol 110 (9) ◽  
pp. 4451-4458 ◽  
Author(s):  
Joanna Makowska ◽  
Katarzyna Bagiñska ◽  
Mariusz Makowski ◽  
Anna Jagielska ◽  
Adam Liwo ◽  
...  
Keyword(s):  
Potentiometric Titration ◽  
Theoretical Methods ◽  
Titration Curves ◽  
Comparison With Experiment

scholarly journals New Histamine-Related Five-Membered N-Heterocycle Derivatives as Carbonic Anhydrase I Activators

Molecules ◽  
2022 ◽  
Vol 27 (2) ◽  
pp. 545
Author(s):  
Niccolò Chiaramonte ◽  
Alessio Gabellini ◽  
Andrea Angeli ◽  
Gianluca Bartolucci ◽  
Laura Braconi ◽  
...  
Keyword(s):  
Carbonic Anhydrase ◽  
Imidazole Ring ◽  
Aliphatic Chain ◽  
Amino Group ◽  
Carbonic Anhydrase I ◽  
Terminal Amino ◽  
Human Carbonic Anhydrase ◽  
New Compounds ◽  
Related Compounds ◽  
Micromolar Range

A series of histamine (HST)-related compounds were synthesized and tested for their activating properties on five physiologically relevant human Carbonic Anhydrase (hCA) isoforms (I, II, Va, VII and XIII). The imidazole ring of HST was replaced with different 5-membered heterocycles and the length of the aliphatic chain was varied. For the most interesting compounds some modifications on the terminal amino group were also performed. The most sensitive isoform to activation was hCA I (KA values in the low micromolar range), but surprisingly none of the new compounds displayed activity on hCA II. Some derivatives (1, 3a and 22) displayed an interesting selectivity for activating hCA I over hCA II, Va, VII and XIII.

Solubility and Complex-Ion Equilibria

2021 ◽  
pp. 313-324
Author(s):  
Christopher O. Oriakhi
Keyword(s):  
Metal Complexes ◽  
Solubility Product ◽  
Formation Constants ◽  
Aqueous Systems ◽  
Complex Ions ◽  
Ionic Compounds ◽  
Molar Solubility ◽  
Solubility Product Constant ◽  
Complex Ion

Solubility and Complex-Ion Equilibria broadens the previous chapter’s coverage of equilibria to include aqueous systems containing two or more solutes of slightly soluble ionic compounds and the formation of metal complexes in solution. Solubility equilibria which allow quantitative predictions of how much of a compound will dissolve under given conditions are covered. The meaning of the solubility product constant (K sp) and how to calculate it from molar solubility values is presented. Also discussed is determination of molar solubility from K sp. Calculations demonstrate how to predict the formation of a precipitate by comparing the ion product or solubility quotient (Q) with K sp. Formation constants of complex ions and calculations involving complex ion equilibria are explained.

scholarly journals Analysis of crystalline and solution states of ligand-free spermidine N-acetyltransferase (SpeG) from Escherichia coli

2019 ◽  
Vol 75 (6) ◽  
pp. 545-553 ◽  
Author(s):  
Ekaterina V. Filippova ◽  
Steven Weigand ◽  
Olga Kiryukhina ◽  
Alan J. Wolfe ◽  
Wayne F. Anderson
Keyword(s):  
Escherichia Coli ◽  
Vibrio Cholerae ◽  
Crystal Structures ◽  
Coenzyme A ◽  
Amino Group ◽  
Acetyl Coenzyme A ◽  
E Coli ◽  
Ligand Free ◽  
Acetyl Group ◽  
Terminal Amino

Spermidine N-acetyltransferase (SpeG) transfers an acetyl group from acetyl-coenzyme A to an N-terminal amino group of intracellular spermidine. This acetylation inactivates spermidine, reducing the polyamine toxicity that tends to occur under certain chemical and physical stresses. The structure of the SpeG protein from Vibrio cholerae has been characterized: while the monomer possesses a structural fold similar to those of other Gcn5-related N-acetyltransferase superfamily members, its dodecameric structure remains exceptional. In this paper, structural analyses of SpeG isolated from Escherichia coli are described. Like V. cholerae SpeG, E. coli SpeG forms dodecamers, as revealed by two crystal structures of the ligand-free E. coli SpeG dodecamer determined at 1.75 and 2.9 Å resolution. Although both V. cholerae SpeG and E. coli SpeG can adopt an asymmetric open dodecameric state, solution analysis showed that the oligomeric composition of ligand-free E. coli SpeG differs from that of ligand-free V. cholerae SpeG. Based on these data, it is proposed that the equilibrium balance of SpeG oligomers in the absence of ligands differs from one species to another and thus might be important for SpeG function.

The Co2 Titration Curve of Mixed Venous Blood

1972 ◽  
Vol 43 (4) ◽  
pp. 553-559 ◽  
Author(s):  
C. T. Kappagoda ◽  
J. B. Stoker ◽  
H. M. Snow ◽  
R. J. Linden
Keyword(s):  
Titration Curve ◽  
Venous Blood ◽  
Mixed Venous Blood ◽  
Ph Values ◽  
Titration Curves ◽  
Mixed Venous

1. Simultaneous CO2 titration curves of arterial and mixed venous blood were determined in both dog and man in vivo. 2. The slopes of the CO2 titration curves of mixed venous blood were significantly less than those of the corresponding arterial curves. 3. The non-respiratory pH values of the CO2 titration curves of mixed venous blood were significantly greater than those of the corresponding arterial curves. 4. The theoretical explanations of these differences have been discussed.

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