Search results for "actin"
showing 10 items of 1375 documents
The Root effect—a physiological perspective
2004
Proteins of Muscle and the Cytoskeleton
1994
The contractile elements of striated vertebrate skeletal muscle, the myofibrils, contain thin filaments, which are 6 nm in diameter and consist mainly of actin, and thicker myosin filaments with a diameter of 16 nm (Fig. 10.1). During muscle contraction, the filaments undergo a sliding movement relative to each other (sliding filament mechanism). This is brought about by the reversible formation of bridges between the myosin molecules and the actin filaments, which bind, change their conformation and then dissociate (bridge cycle). The required energy is supplied by the hydrolysis of ATP. The sliding distance (step size) per molecule of ATP hydrolysed is controversial; the most recent measu…
The toxicity of MCPA to fish. Light and electron microscopy and the chemical analysis of the tissue.
1978
Radioisotopic determination of l-carnitine content in foods commonly eaten in Western countries
2004
Abstract l -Carnitine is a vitamin-like nutrient essential for energy production and lipid metabolism in many organs and tissues such as skeletal muscle and heart. Even if l -carnitine can be synthesized, most of the carnitine present in human body is provided by food. Until now, no large study has been conducted where the content in l -carnitine of various foods was analyzed. The objective of this study was to determine the level of free l -carnitine present in food commonly consumed in Western countries. A radioisotopic assay was used to estimate l -carnitine content in raw and processed foods. From this study, it clearly appeared that meat products were the best sources for l -carnitine.…
Permanent plastid — nuclear complexes (PNCs) in plant cells
2008
Conventional opinion assumes random distribution of plastids in the plant cell and light regulated movement realised with a help of stromules and actin microfilaments. In several organisms from protists to plants the joining of chloroplasts to the nucleus has been mentioned as a phenomenon [1–3]. However, little is known what plants and tissues and how frequently contain these structures? Whether appearance of PNC in cell depends on the state of differentiation? What is physiologic role of the PNC.
Determination of the Stability Constants of the Acetate Complexes of the Actinides Am(III), Th(IV), Np(V), and U(VI) Using Capillary Electrophoresis-…
2019
Capillary electrophoresis-inductively coupled plasma mass spectrometry (CE-ICP-MS) was used to determine the stability constants of the actinides Am(III), Th(IV), Np(V), and U(VI) at an ionic strength of I = 0.3 M. The obtained stability constants were extrapolated to zero ionic strength by means of the Davies equation. For both U(VI) and Am(III), three consecutive acetate complexes with log(β
Two heterologously expressed Planobispora rosea proteins cooperatively induce Streptomyces lividans thiostrepton uptake and storage from the extracel…
2010
Abstract Background A bacterial artificial chromosomal library of Planobispora rosea, a genetically intractable actinomycete strain, was constructed using Escherichia coli-Streptomyces artificial chromosome (ESAC) and screened for the presence of genes known to be involved in the biosynthesis of antibiotics. Results One clone with a 40 kb insert showed antimicrobial activity against Gram positive bacteria. Insert sequence analysis and subcloning experiments revealed that the bioactivity was due to a 3.5 kb DNA fragment containing two open reading frames. These orfs encode two proteins with high similarity to a putative membrane protein of Streptomyces coelicolor and to the nogalamycin resis…
Espressione di galactine nell'infiammazione e nella larva natante di Ciona intestinalis
2010
Characterization of the interaction between Actinin-Associated LIM Protein (ALP) and the rod domain of α-actinin
2009
Abstract Background The PDZ-LIM proteins are a family of signalling adaptors that interact with the actin cross-linking protein, α-actinin, via their PDZ domains or via internal regions between the PDZ and LIM domains. Three of the PDZ-LIM proteins have a conserved 26-residue ZM motif in the internal region, but the structure of the internal region is unknown. Results In this study, using circular dichroism and nuclear magnetic resonance (NMR), we showed that the ALP internal region (residues 107–273) was largely unfolded in solution, but was able to interact with the α-actinin rod domain in vitro, and to co-localize with α-actinin on stress fibres in vivo. NMR analysis revealed that the ti…
Determination of kinetic parameters of redox reactions using CE‐ICP‐MS: A case study for the reduction of Np(V) by hydroxylamine hydrochloride
2018
The rate constants k of the reduction of 5 × 10-5 M Np(V) to Np(IV) by hydroxylamine hydrochloride (HAHCl) in 1 M HCl have been determined by CE-ICP-MS in the temperature range of ϑ = 30-70°C and with varying concentrations of HAHCl from 1 to 7.2 M. The reaction was found to have (pseudo)first order kinetics with respect to HAHCl. The experimental results for k ranged from 0.0029(1) min-1 (ϑ = 40°C, c(HAHCl) = 3 M) to 0.039(7) min-1 (ϑ = 60°C, c(HAHCl) = 7.2 M). The activation energy of the reaction was determined as EA = (72 ± 10) kJ/mol. These results and a comparison with literature data show that the coupling of CE to ICP-MS provides a powerful analytical tool for the investigation of…