213 research outputs found
The CAMP-binding Ectoprotein from Saccharomyces cereuisiae Is Membrane-anchored by Glycosyl-Phosphatidylinositol
Saccharomyces cerevisiae contains an amphiphilic
CAMP-binding glycoprotein at the outer face of the
plasma membrane (M, = 54,000). It is converted to a
hydrophilic form byt reatment withg lycosyl-phosphatidylinositol-
specific phospholipases C and D (GPIPLC/
D), suggesting membrane anchorage by a covalently
bound glycolipid. Determination of the constituents
of the purified anchor by gas-liquid chromatography
and amino acid analysis reveals the presence of
glycerol, myo-inositol, glucosamine, galactose, mannose,
ethanolamine, and asparagine (as the carboxylterminal
amino acido f the Pronase-digested proteitno
which the anchor is attached). Complementary results
are obtained by metabolic labeling, indicating that
fatty acids and phosphorus are additional anchor constituents.
The phosphoruiss resistant to alkalinep hosphatase,
whereas approximately half is lost from the
protein after treatment with GPI-PLD or nitroaucisd ,
and all is removed by aqueous HF indicating the presence
of two phosphodiester bonds. Inhibition of Nglycosylation
by tunicamycin or removal of proteinbound
glycan chains by N-glycanase or Pronase does
not abolish radiolabeling of the anchor structure by
any of the above compounds. Analysis of the products
obtained after sequential enzymic and chemical degradation
of the anchor agrees with the arrangemoefn t
constitutents in GPIs from higher eucaryotes. Evidence
for anchorage of the yeast CAMP-binding protein by a
GPI anchoris strengthened additionallyb y the reactivity
of the GPI-PLC-cleaved anchor with antibodies
directed against the cross-reacting determinoaf nttr ypanosomal
variant surface glycoproteins
A novel type of meso-diaminopimelic acid-based peptidoglycan and novel poly(erythritol phosphate) teichoic acids in cell walls of two coryneform isolates from the surface flora of French cooked cheeses
The primary structure of the peptidoglycan
and the teichoic acids of two coryneform isolates from
the surface flora of French cooked cheeses, CNRZ 925
and CNRZ 926, have been determined. In the peptidoglycan,
meso-diaminopimelic acid was localized in position
three of the peptide subunit. It contained an
D-glutamyl-D-aspartyl interpeptide bridge, connecting
meso-diaminopimelic acid and D-alanine residues of adjacent
peptide subunits. The Alpha-carboxyl group of D-glutamic
acid in position two of peptide subunits was substituted
with glycine amide. The teichoic acid pattern and
composition differed between the strains: both contained
an erythritol teichoic acid and strain CNRZ 925 also
contained an N-acetylglucosaminylphosphate polymer.
The erythritol teichoic acids differed in terms of the
quality and quantity of substituents, but they both had
N,N'-diacetyl-2,3-diamino-2,3-dideoxyglucuronic acid in
common
Band 3 protein—cholesterol interactions in erythrocyte membranes Possible role in anion transport and dependency on membrane phospholipid
AbstractBand 3 protein of the human erythrocyte membrane, the anion transport protein, possesses a high affinity steroid binding site. In mixed phospholipid—cholesterol monolayers, the state of occupancy of this site is positively correlated with their cholesterol and sphingomyelin content and negatively with their glycerophospholipid content. We suggest that, in the erythrocyte membrane, the binding site is an inhibitory site of anion transport and that the modulation of its state of occupancy by the membrane lipid is responsible for the negative correlation of anion transport with the membrane's content of cholesterol and sphingomyelin and the positive correlation with the phosphatidylcholine conten
Phytochemical Characterization and In Vitro Anti-Inflammatory, Antioxidant and Antimicrobial Activity of Combretum Collinum Fresen Leaves Extracts from Benin
Leaves from Combretum collinum Fresen (Combretaceae) are commonly used for the treatment of inflammatory conditions, wound healing and bacterial infections in traditional West African medicine. This research focuses on the characterization of the phenolic profile and lipophilic compounds of leaves extracts of C. collinum. Studies of the in vitro anti-inflammatory activity were performed in TNFα stimulated HaCaT cells and antibacterial activity was evaluated with agar well diffusion and microdilution assays. Antioxidant activity was determined by DPPH and ABTS assays and compared to standards. The phytochemical studies confirmed myricetin-3-O-rhamnoside and myricetin-3-O-glucoside as major components of the leaves extracts, each contributing significantly to the antioxidant activity of the hydrophilic extracts. GC-MS analysis identified 19 substances that were confirmed by comparison with spectral library data and authentic standards. Combretum collinum aqueous leaves extract decreased pro-inflammatory mediators in TNFα stimulated HaCaT cells. Further investigations showed that myricetin-3-O-rhamnoside has an anti-inflammatory effect on IL-8 secretion. In the antimicrobial screening, the largest inhibition zones were found against S. epidermidis, MRSA and S. aureus. MIC values resulted in 275.0 µg/mL for S. epidermidis and 385.5 µg/mL for MRSA. The in vitro anti-inflammatory, antibacterial and antioxidant activity supports topical use of C. collinum leaves extracts in traditional West African medicine
Discrete Adjoint Method for Variational Integration of Constrained ODEs and its application to Optimal Control of Geometrically Exact Beam Dynamics
Direct methods for the simulation of optimal control problems apply a
specific discretization to the dynamics of the problem, and the discrete
adjoint method is suitable to calculate corresponding conditions to approximate
an optimal solution. While the benefits of structure preserving or geometric
methods have been known for decades, their exploration in the context of
optimal control problems is a relatively recent field of research. In this
work, the discrete adjoint method is derived for variational integrators
yielding structure preserving approximations of the dynamics firstly in the ODE
case and secondly for the case in which the dynamics is subject to holonomic
constraints. The convergence rates are illustrated by numerical examples.
Thirdly, the discrete adjoint method is applied to geometrically exact beam
dynamics, represented by a holonomically constrained PDE.Comment: Funding: H2020 Marie-Sk\l{}odowska-Curie 86012
Trinkwasserschutz in Quellgebieten: Handlungsanleitung zur Erstellung von Fachgutachten
Die Broschüre bildet den fachlichen Standard bei der Ausweisung von Trinkwasserschutzgebieten für sächsische Sickerleitungsquellen und deren Speisungsgebiete ab. Sie gibt Hilfestellung bei der Erarbeitung von Fachgutachten und ist an Wasserbehörden, Wasserversorgungsträger, Ingenieurbüros und an die interessierte Öffentlichkeit gerichtet. Als Methodensammlung und als Leitfaden zur Erstellung und Bewertung von Fachgutachten unterstützt sie die Ausweisung von rechtssicheren Trinkwasserschutzgebieten für Sickerleitungsquellen
- …