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Proton-transfer dynamics plays a critical role in many biochemical processes, such as proton pumping across membranes and enzyme catalysis. The large majority of enzymes utilize acid-base catalysis and proton-transfer mechanisms, where the rates of proton transfer can be rate limiting for the overall reaction. However, measurement of proton-exchange kinetics for individual side-chain carboxyl grou

We have found a remarkable relationship between the specificity of antibodies and their chromatographic behavious upon liquid-liquid partition chromatography (LLPC). Well characterized human and murine monoclonal antibodies and Fab/Fv fragments thereof as well as mouse/human chimeric antibodies were employed. While, lgG 1, 2 and 4 antibodies with identical specificities (affinity constants) have i

Cellulose, a polysaccharide consisting of beta-1,4-linked glucose, is the major component of plant cell walls and consequently one of the most abundant biopolymers on earth. Carbohydrate polymers such as cellulose are molecules with vast diversity in structure and function, and a multiplicity of hydrolases operating in concert are required for depolymerisation. The bacterium Rhodothermus marinus,

Popular Abstract in Swedish Cellulosa är ett av de vanligast förekommande biologiska ämnena på jorden och en mycket viktig råvara. Cellulosa är en polymer, uppbyggd av glukosmolekyler som är bundna till varandra i kedjor. Kedjorna kan bli mycket långa och består ofta av flera tusen glukosmolekyler. Eftersom cellulosakedjor är lineära kan de packa sig parallellt med varandra och bilda styva fibrer Soluble derivatives of cellulose have become increasingly important in industrial products e.g. in pharmaceutical applications and in technical dispersions. The polymer characteristics of modified celluloses are to a high degree determined by the substituent distribution along the polymeric backbone. The distribution will be more or less heterogeneous both due to the fact that polymers from renewa

Popular Abstract in Swedish Kemi förknippas ofta med miljöförstöring och gifter och det kan vara lätt att bortse från att dagens samhälle genomsyras och är beroende av produkter tillverkade med kemins hjälp. Läkemedel är exempel på kemiska produkter som alla kommer i kontakt med och i vissa fall inte kan leva utan. Organisk kemi, en viktig undergrupp i det vida begreppet kemi, är en vetenskap som

BACKGROUND: Intestinal ischemia and reperfusion (I/R) injury is a pivotal mechanism in critical illness and in the development of multiple organ dysfunction syndrome, in which the nuclear factor kappa B (NF-κB) activation plays a central role. Intestinal I/R injury initiates the extrinsic tissue factor or factor VIIa-dependent pathway of coagulation, also of importance in multiple organ dysfuncti

Stimulation of rat adipocytes with insulin and isoproterenol results in serine phosphorylation and activation of the adipocyte cGMP-inhibited phosphodiesterase (cGI PDE), events believed to be important in the antilipolytic action of insulin (Degerman, E., Smith, C.J., Tornqvist, H., Vasta, V., Manganiello, V.C., and Belfrage, P. (1990) Proc. Natl. Acad. Sci. U.S.A. 87,533-537). Here we demonstrat

We have investigated the inhibition of the recently identified family C13 cysteine peptidase, pig legumain, by human cystatin C. The cystatin was seen to inhibit enzyme activity by stoichiometric 1:1 binding in competition with substrate. The Ki value for the interaction was 0.20 nM, i.e. cystatin C had an affinity for legumain similar to that for the papain-like family C1 cysteine peptidase, cath

Collagen XVI is integrated tissue-dependently into distinct fibrillar aggregates, such as D-banded cartilage fibrils and fibrillin-1-containing microfibrils. In skin, the distribution of collagen XVI overlaps that of the collagen-binding integrins alpha 1 beta 1 and alpha 2 beta 1. Basal layer keratinocytes express integrin alpha 2 beta 1, whereas integrin alpha 1 beta 1 occurs in smooth muscle ce

The p53 tumor suppressor gene regulates growth arrest and apoptosis after DNA damage. Recent studies suggest that p53 is inactive in vascular smooth muscle cells (VSMCs) in human angioplasty restenosis, promoting VSMC accumulation and vessel stenosis. In contrast, the success of irradiation (brachytherapy) for in-stent restenosis argues that DNA-damage p53 responses are intact. We examined p53 exp

The chemical composition of foraminiferal calcite is widely used for studying past environmental conditions and biogeochemistry. However, high rates of microbial organic matter degradation and abundant dissolved metal sources in sediments and pore waters may impede the application of foraminifera-based proxies due to formation of secondary carbonates or other authigenic minerals on and/or inside o

Petrochemical enterprises in Kazakhstan discharge polluted wastewater into special recipients. Contaminants infiltrate through the soil into the groundwater, which potentially affects public health and environment safety. This paper presents the evaluation of a 7-year monitoring program from one of the factories and includes nineteen variables from nine wells during 2013–2019. Several multivariate