Low Protein Levels (low + protein_level)

Distribution by Scientific Domains


Selected Abstracts


CoagMDB: a database analysis of missense mutations within four conserved domains in five vitamin K,dependent coagulation serine proteases using a text-mining tool,

HUMAN MUTATION, Issue 3 2008
Rebecca E. Saunders
Abstract Central repositories of mutations that combine structural, sequence, and phenotypic information in related proteins will facilitate the diagnosis and molecular understanding of diseases associated with them. Coagulation involves the sequential activation of serine proteases and regulators in order to yield stable blood clots while maintaining hemostasis. Five coagulation serine proteases,factor VII (F7), factor IX (F9), factor X (F10), protein C (PROC), and thrombin (F2),exhibit high sequence similarities and all require vitamin K. All five of these were incorporated into an interactive database of mutations named CoagMDB (http://www.coagMDB.org; last accessed: 9 August 2007). The large number of mutations involved (especially for factor IX) and the increasing problem of out-of-date databases required the development of new database management tools. A text mining tool automatically scans full-length references to identify and extract mutations. High recall rates between 96 and 99% and precision rates of 87 to 93% were achieved. Text mining significantly reduces the time and expertise required to maintain the databases and offers a solution to the problem of locus-specific database management and upkeep. A total of 875 mutations were extracted from 1,279 literature sources. Of these, 116 correspond to Gla domains, 86 to the N-terminal EGF domain, 73 to the C-terminal EGF domain, and 477 to the serine protease domain. The combination of text mining and consensus domain structures enables mutations to be correlated with experimentally-measurable phenotypes based on either low protein levels (Type I) or reduced functional activities (Type II), respectively. A tendency for the conservation of phenotype with structural location was identified. Hum Mutat 29(3), 333,344, 2008. © 2007 Wiley-Liss, Inc. [source]


Semiquantitative analysis of urinary low protein levels using silver dot blot assay

JOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 4 2001
Kazuyuki Matsuda
Abstract We designed a semiquantitative analysis of urinary low protein levels using silver dot blot assay. In this method, 3 ,l of urine are blotted to one dot onto a cellulose acetate membrane, which is stained by a colloidal silver staining reagent, and the optical density of the silver stained urinary protein is measured at 500 nm using a densitometer. There was a good linearity between 2.5 mg/L and 100 mg/L and a gentle linearity between 100 mg/L and 200 mg/L, and the minimum sensitivity was 2.5 mg/L. This method is suitable for semiquantitative analysis of urinary protein levels less than 300 mg/L, which can not be determined precisely by dipstick. J. Clin. Lab. Anal. 15:171,174, 2001. © 2001 Wiley-Liss, Inc. [source]


Carbonate extraction process for the metabolic, isozymic and proteomic profiling of rose-scented geranium (Pelargonium sp.), a hyper-acidic plant

PHYTOCHEMICAL ANALYSIS, Issue 2 2008
Rajender Singh Sangwan
Abstract Rose-scented geranium (Pelargonium sp.) is a valuable monoterpene-yielding plant. It has been well characterised phytochemically through the isolation of >270 secondary metabolites, however, there is hardly any biochemical or metabolic information concerning this plant. Initial attempts to investigate its metabolism failed to produce any enzyme activity in the tissue extracts prepared in routine extraction buffers owing to the intrinsic properties of the tissue matrix. It was recognised that cellular hyper-acidity (cell sap pH ,3.0) gave rise to very low protein levels in the extracts, thus prohibiting detection of activities of even primary metabolic enzymes that are usually abundantly present in plants. Tissue extraction in Tris solution without pH adjustment (as used for studies involving citrus and banana) led to little or no improvement. Therefore, a novel approach using sodium carbonate solution as an efficient extraction system for enzymes and proteins from the plant was studied. Functionality of the carbonate extraction has been demonstrated through its effectiveness, a several-fold superior performance, in yielding protein, monitoring primary metabolism and secondary metabolic enzymes, and isozymic and polypeptide profiling. The process may also be helpful in the reliable analysis of other acidic plant tissues. Copyright © 2007 John Wiley & Sons, Ltd. [source]


Control of the release of digestive enzymes in the larvae of the fall armyworm, Spodoptera frugiperda

ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY (ELECTRONIC), Issue 1 2010
Digali Lwalaba
Abstract There is a basal level of enzyme activity for trypsin, aminopeptidase, amylase, and lipase in the gut of unfed larval (L6) Spodoptera frugiperda. Trypsin activity does not decrease with non-feeding, possibly because of the low protein levels in plants along with high amino acid requirements for growth and storage (for later reproduction in adults). Therefore, trypsin must always be present so that only a minimal protein loss via egestion occurs. Larvae, however, adjust amylase activity to carbohydrate ingestion, and indeed amylase activity is five-fold higher in fed larvae compared to unfed larvae. Gut lipase activity is low, typical of insects with a high carbohydrate diet. A flat-sheet preparation of the ventriculus was used to measure the release of enzymes in response to specific nutrients and known brain/gut hormones in S. frugiperda. Sugars greatly increase (>300%) amylase release, but starch has no effect. Proteins and amino acids have little or no effect on trypsin or aminopeptidase release. The control of enzyme release in response to food is likely mediated through neurohormones. Indeed, an allatostatin (Spofr-AS A5) inhibits amylase and trypsin, and allatotropin (Manse- AT) stimulates amylase and trypsin release. Spofr-AS A5 also inhibits ileum myoactivity and Manse-AT stimulates myoactivity. The epithelial secretion rate of amylase and trypsin was about 20% of the amount of enzyme present in the ventricular lumen, which, considering the efficient counter-current recycling of enzymes, suggests that the secretion rate is adequate to replace egested enzymes. © 2009 Wiley Periodicals, Inc. [source]