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: I. Isolation and composition of acetylhexosamine and acetylhexosamine-peptide complexes

in Biochimica et Biophysica Acta (1960), 40

Some of the dialyzable products of the digestion of Micrococcus lysodeikticus cell walls by lysozyme and by a similar enzyme secreted by a Streptomyces have been isolated and their compositions determined ... [more ▼]

Some of the dialyzable products of the digestion of Micrococcus lysodeikticus cell walls by lysozyme and by a similar enzyme secreted by a Streptomyces have been isolated and their compositions determined. The two simplest substances released by both enzymes are (a) a di-saccharide of N-acetylmuramic acid-N-acetylglucosamine and (b) an N-acetylmuramic acid-N-acetylglucosamine complex. Seven peptide-acetyl-amino sugar complexes have been isolated. All seven compounds contain lysine, glutamic acid, glycine, alanine in the same molecular proportions as found in the original cell wall and a di-saccharide moiety of N-acetylmuramic acid and N-acetylglucosamine. One of the peptide-amino sugar complexes contains in addition a polysaccharide moiety [N-acetylmuramic acid-N-acetylglucosamine]10. [less ▲]

Quelques réflexions d'un spectroscopiste

in Annales d'astrophysique (1960), 23

Individual spectroscopic studies are of great importance. Spectroscopic observations in the infra-red and for ultra-violet should be prepared and our knowledge of spectroscopic properties in classical ... [more ▼]

Individual spectroscopic studies are of great importance. Spectroscopic observations in the infra-red and for ultra-violet should be prepared and our knowledge of spectroscopic properties in classical fields should also be improved in order to find solutions to the following problems : interstellar matter, planetary nebulae, symbiotic stars, W, Of and Be stars, relative abundances in stars of population type II, isotopic abundances in stars and planets, variable stars, etc.... [less ▲]

Particules inconnues I

in Bulletin de l'Académie Royale des Sciences, des Lettres et des Beaux-Arts de Belgique. Sciences (1960), 46

The possible existence of undiscovered elementary particles is discussed. The electric charge Q an the "neutrinonic charge" R, introduced in a preceding paper, are given for two such particles, which are ... [more ▼]

The possible existence of undiscovered elementary particles is discussed. The electric charge Q an the "neutrinonic charge" R, introduced in a preceding paper, are given for two such particles, which are baryons: Q=1, R=0 and Q=-1, R=-2; for the newly discovered D-meson, they are Q=1, R=1. [less ▲]

Développements en séries de Fourier

Learning material (1960)

Mécanisme d'excitation des bandes de Swan des comètes

in Annales d'astrophysique (1960), 23

The high resolution spectrograms of Comet Mrkos (1957d) reveal the essential features of the rotational structure of the Swan-bands. Intensity anomalies observed within the (1 - 0) and (2 - 1) transitions ... [more ▼]

The high resolution spectrograms of Comet Mrkos (1957d) reveal the essential features of the rotational structure of the Swan-bands. Intensity anomalies observed within the (1 - 0) and (2 - 1) transitions are due to the presence of absorption lines in the exciting solar radiation. It is thus proved that the Swan bands are excited by fluorescence, although their lower level 3πu is not the ground electronic state of C2. [less ▲]

La pédagogie de Niemeyer

Doctoral thesis (1960)

Les observations astronomiques au dehors de l’atmosphère terrestre

Book published by Centre National de Recherches de l’Espace. (1960)