PubMed Health⌕ Search
Home/Archive/PubMed

PubMed · 7663376

B-hematin.

G Blauer·M Akkawi
View original source ↗Export metadata ↓

Abstract

Very rapid production in vitro of a particular type of hematin (B-hematin) with high yield at physiological pH and temperature is presently reported, using a simple chemical system including an organic acid in the absence of any enzyme. B-hematin is characterized by infrared spectra and solubility properties. The antimalarial drug chloroquine practically prevents formation of this hematin under the conditions used. It has recently been suggested that the purified malaria pigment hemozoin is identical with beta-hematin, a form of ferriprotoporphyrin IX sparingly soluble in different solvents which is prepared under non-physiological conditions. Relations between B- and beta-hematin and possible mechanisms of hemozoin formation and antimalarial drug action, are discussed.

Explore related subjects

AcetatesAcetic AcidChloroquineHemeproteinsHeminKineticsPigments, BiologicalSolubilitySpectroscopy, Fourier Transform InfraredComparative StudyJournal Article

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

G Blauer, M Akkawi. 1995. B-hematin.. https://pubmed.ncbi.nlm.nih.gov/7663376/

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed1997

Biosynthesis of mycothiol: elucidation of the sequence of steps in Mycobacterium smegmatis.

Several members of the Actinomycetales, including the medically important mycobacteria, produce 1-D-myo-inosityl-2-(N-acetyl-L-cysteinyl)amino-2-deoxy-alpha-D- glucop yranoside (trivial name mycothiol) as their principal low-molecular-mass thiol. The pseudo-disaccharide component of mycothiol, 1-D-myo-inosityl-2-amino-2-deoxy-alpha-D-glucopyranoside (alpha-D-GI), was synthesized by ligation of 1-D,L-2,3,4,5, 6-penta-O-acetyl-myo-inositol to 3,4,6-tri-O-acetyl-2-deoxy- 2-(2,4-dinitrophenylamino)-alpha-D-glu- copyranosyl bromide to give, in the first instance, an isomeric mixture of alpha- and beta-linked pseudo-disaccharides. The alpha-coupled D,D and D,L isomers, alpha-D-GI and alpha-L-GI respectively, were purified from the mixture by TLC, followed by removal of the protecting groups. A cell-free extract of Mycobacterium smegmatis catalysed the ligation of cysteine, acetate and alpha-D-GI in the presence of ATP and Mg2+ to form mycothiol, as judged by HPLC. When no acetate was added to the incubation mixture, an additional thiol accumulated. In the presence of [14C]acetate no radiolabel was recovered in this species, but only in mycothiol. The additional thiol was isolated as the bimane derivative, and 1H and 1H-1H COSY NMR spectra confirmed its identity as desacetylmycothiol. A more complete conversion of desacetylmycothiol into mycothiol was achieved in the presence of acetyl-S-CoA. These results indicate that the biosynthesis of mycothiol proceeds by the sequential addition of cysteine and acetate to alpha-D-GI. The inositol moiety appears to be an important determinant of specificity, since alpha-L-GI was poorly utilized.

Acetates↗
PubMed1997

2-Methyl-3-oxo-4-phenyl-2,3-dihydrofuran-2-yl acetate: a fluorogenic reagent for detection and analysis of primary amines.

A new fluorogenic reagent, 2-methyl-3-oxo-4-phenyl-2,3-dihydrofuran-2-yl acetate, has been developed for the analysis of primary amines and aminated carbohydrates by means of HPLC, CE, and MALDI/MS. Peptides at 1 pmol (2 x 10(-7) M) levels were successfully labeled and analyzed through CE. The fluorescent derivatives have good stability in both acidic and basic solutions, making their further manipulation and structural analysis possible. The derivatives can be analyzed in reversed-phase HPLC due to the hydrophobic nature of this fluorescent tag. Characteristic elution intervals between the diastereomeric peaks of the chiral peptide derivatives may be used in structural verification. The labeled peptides and neutral oligosaccharides are also readily detectable through MALDI/MS in its positive mode.

Acetates↗
PubMed1997

Interwoven hydrogen-bonding networks in benzene-1,3,5-triacetic acid.

The title compound, C12H12O6, crystallized in the centrosymmetric space group P21/n. Each molecule is hydrogen bonded to four others by ten hydrogen bonds forming a three-dimensional network. Two sets of such networks, which are not linked, comprise the structure. The carboxyl O atoms are ordered, as are the carboxyl H atoms. The best-fit acetic acid group planes make dihedral angles of 84.3 (1), 89.8 (2) and 58.0 (2) degrees with the best-fit benzene core plane.

Acetates↗