Structure of the cell wall of Staphylococcus aureus, strain Copenhagen. I. Preparation of fragments by enzymic hydrolysis

in Biochemistry (1963), 2(5), 11101119

The cell wall of S. aureus strain Copenhagen, has been solubilized through the action of the 32 enzyme" isolated from Streptomyces albus G. This solubilization was the consequence of hydrolysis of ... [more ▼]

The cell wall of S. aureus strain Copenhagen, has been solubilized through the action of the 32 enzyme" isolated from Streptomyces albus G. This solubilization was the consequence of hydrolysis of acetylamino sugar linkages in the cell wall [less ▲]

Purification de la [beta]-(1-4)-N-acétylhexosaminidase sécrétée par Streptomyces albus G et active sur les parois de Micrococus lysodeikticus

in Biochimica et Biophysica Acta (1962), 58

The N-acetylhexosaminidase (referred as Str) secreted by Streptomyces albus G. has been purified by zone electrophoresis. It is slightly less basic than egg-white lysozyme. Its isoelectric point is close ... [more ▼]

The N-acetylhexosaminidase (referred as Str) secreted by Streptomyces albus G. has been purified by zone electrophoresis. It is slightly less basic than egg-white lysozyme. Its isoelectric point is close to pH 10.3. It has no action on the [alpha]- and [beta]-phenylglycosides of N-acetylglucosamine and on the disaccharides [beta]-(1-4)-di-N-acetylglucosamine (di-N-acetylchitobiose) and [beta]-(1-6)-N-acetylglucosaminyl-N-acetylmuramic acid but it splits the tetrasaccharide [beta]-(1-4)-tetra-N-acetylglucosamine(tetra-N-acetylchitotetraose) in di-N-acetylchitobiose. Contrary to lysozyme, it does not split the tetrasaccharide O-[beta]-N-acetylglucosaminyl-(1-6)-O-[beta]-N-acetylmuraminyl-(1-4)-O-[beta]-N-acetylglucosaminyl-(1-6)-[beta]-N-acetylmuramic acid in disaccharide by hydrolyzing the [beta](1-4) linkage. In those conditions the disaccharide liberated, as well as the tetrasaccharide, from Microccus lysodeikticus cell walls after incubation with the N-acetylhexosaminidase Str, can not be put down to a further digestion of some tetrasaccharidic fragments. A chitobiase only active on the [beta]-phenyl-glycoside of N-acetylglucosamine and on the di-N-acetylchitobiose is also present in contentrated culture filtrates. It is a protein acid at pH 6.6. [less ▲]

Complexe acide téichoique-mucopeptide des parois cellulaires de Bacillus megaterium KM

in Biochimica et Biophysica Acta (1961), 50(3), 413-429

Walls of a batch of Bacillus megalerium KM contain a polyol phosphate compound which, in contrast with BADDILEY'S teichoic acids, is not extracted by cold tri-chloroacetic acid. It has been isolated by ... [more ▼]

Walls of a batch of Bacillus megalerium KM contain a polyol phosphate compound which, in contrast with BADDILEY'S teichoic acids, is not extracted by cold tri-chloroacetic acid. It has been isolated by paper electrorheophoresis from the non-dialysable fraction obtained after incubation of the walls by lysozyme. Owing to the chemical analysis, it is associated with mucopeptide residues and the whole complex represents 40%, dry weight, of the walls. The degradation of this complex by two Streptomyces enzymes enables the identi-fication of three fragments: a teichoic fragment of polyol phosphate, glucose and N-acetylglucosamine; a mucopeptide fragment of amino acids and N-acetylmuramic acid; a disaccharide fragment 6-O-fl-N-acetylglucosaminyl-N-acetyl-muramic acid. It is believed that the latter represents an unit of a poly-N-acetylhexosamine back-bone of the basal mucopeptide of the wall. The teichoic fragment is liberated from the whole colnplex under the action of both Streptomyces enzymic preparations FI or F2B. It can also be obtained by in-cubating directly the walls with each of those preparations. The disaccharide fragment is liberated under the action of the F2B amidase. Approx. 6 %, dry weight, of the walls consist of glucose (probably a polyglucose) non associated with the teichoic acid-mucopeptide complex. N-acetylmuramic acid and various oligosaccharides consisting of N-acetyl- glucosamine alone or of both N-acetylglucosamine and N-acetylmuramic acid, give, on paper, a pink coloration with the diphenylamine-trichloroacetic reagent which allows them to be distinguished from N-acetylglucosamine. [less ▲]

Acetylhexosamine compounds enzymically released from Micrococcus lysodeikticus cell walls: III. The structure of di- and tetra-saccharides released from cell walls by lysozyme and Streptomyces F1 enzyme

in Biochimica et Biophysica Acta (1960), 45

Two compounds, both of which have been isolated from cell walls of Micrococcus lysodeikticus digested with lysozyme or Streptomyces F1 enzyme, have been identified as di- and tetra-saccharides. The ... [more ▼]

Two compounds, both of which have been isolated from cell walls of Micrococcus lysodeikticus digested with lysozyme or Streptomyces F1 enzyme, have been identified as di- and tetra-saccharides. The reducing groups of the di- and tetra-saccharides and those of the high-molecular weight, non-dialysable compounds belong to muramic acid. [beta]-glucosidase yields free N-acetylglucosamine and N-acetylmuramic acid from the di- and tetra-saccharides. The proposed structure for the di-saccharide liberated by lysozyme and F1 is: 6-O-[beta]-N-acetylglucosaminyl-N-acetylmuramic acid. The tetra-saccharides isolated from lysozyme and F1 digests appear to be identical. The structure proposed for the tetra-saccharide isolated from lysozyme digested walls is: O-[beta]-N-acetylglucosaminyl-(I-->6)-O-[beta]-N-acetylmuraminyl-(I-->4)-O-[beta]-N-acetylglucosaminyl- (I-->6)-[beta]-N-acetylmuramic acid. Both lysozyme and Streptomyces F1 enzyme degrade di- and tetra-chitobiose, indicating their [beta](I-->4) N-acetyl hexosaminidase activity. [less ▲]

Acetylhexosamine compounds enzymically released from micrococcus lysodeikticus cell walls: II. Enzymic sensitivity of purified acetylhexosamine and acetylhexosamine-peptide complexes

in Biochimica et Biophysica Acta (1960), 40

Effet de la mescaline, du lsd 25 et de dérivés de l'adrenochrome sur la décarboxlyase glutamique du cerveau

in Biochemical Pharmacology (1959), 1(4), 267-272

The inhibitory effect of adrenochrome on glutamic decarboxylase from brain homogenates in vitro, does not occur with mescaline and LSD 25. Certain stable derivatives of adrenochrome such as MSCA and AHA ... [more ▼]

The inhibitory effect of adrenochrome on glutamic decarboxylase from brain homogenates in vitro, does not occur with mescaline and LSD 25. Certain stable derivatives of adrenochrome such as MSCA and AHA, in which the quinonic function is blocked, have an opposite effect, and behave like activators of brain glutamic decarboxylase. This activation seems to be indirect; MSCA and AHA do not constitute new coenzymes. [less ▲]

Les activités antimicrobiennes des détergents

in Revue Médicale de Liège (1957), 12(17), 457-464

Action de l'actinomycétine sur les parois cellulaires bactériennes

in Biochimica et Biophysica Acta (1957), 24(1), 160-173

Action de l'actinomycetine sur les parois cellulaires bacteriennes

in Biochimica et Biophysica Acta (1957), 24

The cell walls of a number of gram-positive bacteria can be digested by two different enzymes, present in actinomycetin, which have been obtained in a purified form. In contrast to lysozyme and the ... [more ▼]

The cell walls of a number of gram-positive bacteria can be digested by two different enzymes, present in actinomycetin, which have been obtained in a purified form. In contrast to lysozyme and the streptolytic enzyme of McCarty, these two enzymes are peptidases, their lytic action on the cell walls being accompanied by the liberation of alanine and/or glycine and small dialysable peptides. The ionic strength of the medium plays an essential role in the lysis. This role has been described and it probably depends on the electric charge of the cell walls. The products of the digestion of cell walls of staphylococci have been specially studied: at least some of the liberated alanine has the D-form; the non-dialysable fractions have been examined by electrophoresis and by ultra-centrifugation. [less ▲]

Concentration et purification des principes bacteriolytiques de l'actinomycetine par chromatographie sur corps microbiens.

in Comptes Rendus des Séances de la Société de Biologie et de ses Filiales (1954), 148(13-14), 1283-1287