Studies on lipopolysaccharides of Proteus

1971 ◽  
Vol 17 (11) ◽  
pp. 1385-1394 ◽  
Author(s):  
B. A. Dmitriev ◽  
N. A. Hinton ◽  
R. W. Lowe ◽  
J. K. N. Jones

The polysaccharide moieties of the lipopolysaccharides of serotyped strains of Proteus have been examined. The strains were selected to provide a wide range of serotypes. The primary acetic acid extracts of different strains of Proteus were fractionated on Sephadex G-50 and yielded three main components: a peak (I), which was composed mainly of polysaccharide; a second peak (II), the core polysaccharide, which contained heptose and phosphate; and a third component (III), which corresponded to a low molecular weight fraction and contained KDO and phosphate as well as other components. Peak I was not encountered in rough strains of Proteus. The chemical composition of the peaks obtained for S, SR, and R strains is discussed in relation to their agglutinating ability to homologous antiserum.

1981 ◽  
Vol 46 (03) ◽  
pp. 612-616 ◽  
Author(s):  
U Schmitz-Huebner ◽  
L Balleisen ◽  
F Asbeck ◽  
J van de Loo

SummaryHigh and low molecular weight heparin fractions obtained by gel filtration chromatography of sodium mucosal heparin were injected subcutaneously into six healthy volunteers and compared with the unfractionated substance in a cross-over trial. Equal doses of 5,000 U were administered twice daily over a period of three days and heparin activity was repeatedly controlled before and 2, 4, 8 hrs after injection by means of the APTT, the anti-Xa clotting test and a chromogenic substrate assay. In addition, the in vivo effect of subcutaneously administered fractionated heparin on platelet function was examined on three of the volunteers. The results show that s.c. injections of the low molecular weight fraction induced markedly higher anti-Xa activity than injections of the other preparations. At the same time, APTT results did not significantly differ. Unfractionated heparin and the high molecular weight fraction enhanced ADP-induced platelet aggregation and collagen-mediated MDA production, while the low molecular weight fraction hardly affected these assays, but potently inhibited thrombin-induced MDA production. All heparin preparations stimulated the release of platelet Factor 4 in plasma. During the three-day treatment periods, no side-effects and no significant changes in the response to heparin injections were detected.


2007 ◽  
Vol 28 (10) ◽  
pp. 2149-2153 ◽  
Author(s):  
Radoslav Goldman ◽  
Habtom W. Ressom ◽  
Mohamed Abdel-Hamid ◽  
Lenka Goldman ◽  
Antai Wang ◽  
...  

2004 ◽  
Vol 49 (9) ◽  
pp. 257-265 ◽  
Author(s):  
C. Hepplewhite ◽  
G. Newcombe ◽  
D.R.U. Knappe

The adsorption of an odour compound common in drinking water, 2-methylisoborneol (MIB), was studied on two activated carbons in the presence of 13 well-characterised natural organic matter (NOM) solutions. It was found that, although the carbons and the NOM solutions had a wide range of characteristics, the major competitive mechanism was the same in all cases. The low molecular weight NOM compounds were the most competitive, participating in a direct competition with the MIB molecule for adsorption sites. Equivalent background concentration (EBC) calculations indicated a relatively low concentration of directly competing compounds in the NOM. Some evidence of pore restriction was also seen, with microporous carbons most affected by low molecular weight NOM, and mesoporous carbons impacted by the higher molecular weight compounds.


2015 ◽  
Vol 37 (1) ◽  
pp. 55-67 ◽  
Author(s):  
Gregory W. Thomas ◽  
Leonard T. Rael ◽  
Charles W. Mains ◽  
Denetta Slone ◽  
Matthew M. Carrick ◽  
...  

1997 ◽  
Vol 70 (5) ◽  
pp. 707-713 ◽  
Author(s):  
Jitladda Tangpakdee ◽  
Yasukuki Tanaka

Abstract The gel content of rubber from high-ammonia latex (HA-latex) decreased significantly after deproteinization with proteolytic enzyme. The addition of 1–2% ethanol in toluene solution reduced the gel content of rubbers from HA-latex, deproteinized HA-latex (HA-DP) and pale crepe. Transesterification of the rubber in toluene solution with sodium methoxide dissolved the gel fraction. The gel fractions solubilized after transesterification showed molecular weight distribution rich in low molecular-weight fraction. The Huggins k′ constant of the fractionated rubbers from solubilized-gels was in the range of 0.42–0.45, lower than that of the fractionated HA-DP of 0.5–0.8. This indicates that all the branch-points were decomposed by transesterification to form linear molecules. The Mn values of rubber chains assembling the gel was 5.5−8.3×105 by 13C-NMR measurements of the ratio between cis- and trans-isoprene units, which were comparable to the molecular weight between crosslinks, Mc, of 7−11×105 by swelling measurements. These findings suggest that the branching and crosslinks are composed of two types of branch-points, i. e. one by association or aggregation of proteins or oligopeptides at the initiating end and the other by ester linkages including phosphoric ester at the terminal end.


Holzforschung ◽  
2002 ◽  
Vol 56 (2) ◽  
pp. 199-208 ◽  
Author(s):  
Thomas Rosenau ◽  
Antje Potthast ◽  
Andreas Hofinger ◽  
Herbert Sixta ◽  
Paul Kosma

Summary Polonowski type degradation reactions are a major reason for the frequently observed instability of solutions of cellulose in N-methylmorpholine-N-oxide monohydrate (NMMO, 1). The degradation is induced by degradation products of cellulose and NMMO generated in situ in the Lyocell system. The presence of both an amine component, such as morpholine or N-methylmorpholine, and an acid component is required for the decomposition process to proceed. The latter might be a low-molecular-weight compound, such as formic acid, acetic acid or gluconic acid, or also a high-molecular-weight acid, such as polyglucuronic acid or ion exchange resin.


2007 ◽  
Vol 54 (9) ◽  
pp. 419-423 ◽  
Author(s):  
Kyosuke Yamamoto ◽  
Yoshihiro Nishikawa ◽  
Takashi Kimura ◽  
Munehiko Dombo ◽  
Nariaki Matsuura ◽  
...  

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