Interaction between acidic activation domains and the activator-binding
domains of Swi1 and Snf5 of the yeast SWI⁄SNF chromatin remodeling
complex has previously been characterized in vitro. Although deletion of
both activator-binding domains leads to phenotypes that differ from the
wild-type, their relative importance for SWI⁄SNF recruitment to target
genes has not been investigated.
Ongoing scientific research in many parts of the world on the genomics, proteomics and genetic engineering of LAB is increasing our understanding of their physiology, pushing further the boundaries for their potential applications. "Lactic Acid Bacteria - R&D for Food, Health & Livestock Purposes" is a compilation and discussion of the outstanding scientific research activities concerning actually and future applications of LAB. It is directed to a vast public of readers - researcher, academics, corporate R&D, students or just curious interested in the subject....
The effect of polyaspartate (PASP) on the performance of the lead-acid negative plate has been investigated. It was established that this polymer additive controls the crystallization process of lead sulphate and modiﬁes the shape and size of PbSO4 crystals. The addition of PASP to the negative paste and to the electrolyte improves the utilization of the negative active material and reduces the internal resistance of the negative plates.
Some years ago a consortium of enterprises and a university from different European countries and industrial sectors was established
to work together in the development of lighter lead–acid batteries for electrical and conventional vehicles with new innovative materials
and process techniques, with the final goal of increasing the energy density by means of a battery weight reduction. Its main idea was to
substitute the heavy lead alloy grids mechanical support of the active masses and collectors of the current produced during the charge
and discharge reactions.
In the past several years, there have been many developments in the materials for lead–acid batteries. Silver in grid alloys for high temperature climates in SLI batteries has increased the silver content of the recycled lead stream. Concern about silver and other contaminants in lead for the active material for VRLA batteries led to the initiation of a study by ALABC at CSIRO. The study evaluated the effects of many different impurities on the hydrogen and oxygen evolution currents in ﬂoat service for ﬂooded and VRLA batteries at different temperatures and potentials. ...
Performance of a valve regulated lead/acid battery is affected by the properties of the positive grid corrosion layer. An investigation has been carried out using a range of experimental techniques to study the inﬂuence of corrosion layer composition and structure on cyclic performance. A number of designs of battery were manufactured with different grids and positive active materials (PAMs).
Pb–Ca foil laminated on rolled sheet for positive grid of lead-acid battery is proposed to prevent premature capacity loss (PCL) during charge–discharge cycling. Batteries with Pb–Ca foil laminated on positive grid had longer life during charge–discharge cycle than conventional battery, which failed early by PCL. PCL is a phenomenon due to the increase of the interfacial resistance between the positive grid and the positive active mass (PAM) during discharging by PbSO4 formation in the corrosion layer....
The study looked at the use of red lead in the manufacturing of valve regulated lead acid (VRLA) miners cap lamp (MCL) batteries that were made with either ﬂat plate or tubular positive electrodes. A problem with using only grey oxide in the manufacture of thick ﬂat plate or tubular electrodes is the poor conversion of the active material to the desired lead dioxide.
The innovative solution proposed in this paper to improve both cycling life and performances of a very low cost lead–acid battery is the combination of the compression concept and the use of micro-porous additives added in the active mass.
This Acid rain and its effects presents: Definition Acid rain, Emissions of chemicals leading to acidification, Natural phenomena, Human activity, Chemical processes to form acid rain, Measuring Acid Rain, Adverse effects,..
To investigate the role of protein–protein and protein–nucleic acid interac-tions in virus assembly, we compared the stabilities of native bacteriophage
MS2, virus-like particles (VLPs) containing nonviral RNAs, and an assem-bly-defective coat protein mutant (dlFG) and its single-chain variant
Exposure to quartz particles induces a pathological process named silicosis.
Alveolar macrophages initiate the disease through their activation, which is
the origin of the later dysfunctions. Ascorbic acid is known to selectively
dissolve the quartz surface. During the reaction, ascorbic acid progressively
disappears and hydroxyl radicals are generated from the quartz surface.
These observations may be relevant to mammalian quartz toxicity, as sub-stantial amounts of ascorbic acid are present in the lung epithelium. ...
Departamento de Fisiologıa de la Nutricion, Instituto Nacional de Ciencias Medicas y Nutricion ‘Salvador Zubiran’, Mexico; ´ ´ ´ ´ ´ Departamento de Patologıa Experimental, Instituto Nacional de Ciencias Medicas y Nutricion ‘Salvador Zubiran’,Mexico; 3Department of Biochemistry, Wake Forest University Medical Center, Winston-Salem, North Carolina, USA
Branched chain amino-acid aminotransferase (BCAT) activity is present in fetal liver but the developmental pattern of mitochondrial BCAT (BCATm) expression in rat liver has not been studied.
The bacterial twin-arginine translocation (Tat) system is a protein targeting
pathway dedicated to the transport of folded proteins across the cytoplas-mic membrane. Proteins transported on the Tat pathway are synthesised as
precursors with N-terminal signal peptides containing a conserved amino
Glutaminase from Micrococcus luteusK-3 [Micrococcusglutaminase
(Mglu); 456 amino acid residues (aa); 48 kDa] is a salt-tolerant enzyme. Our
previous study determined the structure of its major 42-kDa fragment. Here,
using new crystallization conditions, we determined the structures of the
intact enzyme in the presence and absence of its product l-glutamate and its
activator Tris, which activates the enzyme by sixfold.
Unusually among ATP-binding cassette proteins, the sulfonylurea receptor
(SUR) acts as a channel regulator. ATP-sensitive potassium channels are
octameric complexes composed of four pore-forming Kir6.2 subunits and
four regulatory SUR subunits. Two different genes encode SUR1 (ABCC8)
and SUR2 (ABCC9), with the latter being differentially spliced to give
SUR2A and SUR2B, which differ only in their C-terminal 42 amino acids.
Retinoic acid receptor (RAR) and retinoid X receptor are ligand-induced
transcription factors that belong to the nuclear receptor family. The
receptors are activated by small hydrophobic compounds, such as
all-trans-retinoic acid and 9-cis-retinoic acid, respectively. Interestingly,
these receptors are also targets for a number of exogenous compounds.
Thrombi, which are dissolved primarily by plasmin (EC 126.96.36.199.), contain
up to millimolar concentrations of fatty acids and these are known to
affect the action of the protease. In the present study the modulation of
plasmin activity was characterized quantitatively in a continuous amidolytic
assay based on synthetic plasmin substrate (Spectrozyme-PL).
Sphingolipid activator proteins (SAPs), GM2 activator protein (GM2AP)
and saposins (Saps) A–D are small, enzymatically inactive glycoproteins of
the lysosome. Despite of their sequence homology, these lipid-binding and
-transfer proteins show different specificities and varying modes of action.
Water-soluble SAPs facilitate the degradation of membrane-bound glyco-sphingolipids with short oligosaccharide chains by exohydrolases at the
The human UDP-glucuronosyltransferase (UGT) isoforms UGT2B4 and
UGT2B7 play a major role in the detoxification of bile acids, steroids and
phenols. These two isoforms present distinct but overlapping substrate spe-cificity, sharing common substrates such as the bile acid hyodeoxycholic
acid (HDCA) and catechol-estrogens.