During the last decade new ionization techniques have made it possible to measure molecular weight of many intact proteins by mass spectrometry, and they much easier obtain a spectrometric peptide map protein. At same time advances in protein DNA sequencing technology are resulting an exponential increase number sequences deposited databases. Here we investigate possibility use data identify Searching database total is found be easy sometimes sufficient approach. For more specificity for...

Angiostatin, a proteolytic fragment of plasminogen, is potent antagonist angiogenesis and an inhibitor endothelial cell migration proliferation. To determine whether the mechanism by which angiostatin inhibits and/or proliferation involves binding to surface plasminogen receptors, we isolated proteins for from human umbilical vein cells. Binding studies demonstrated that bound in concentration-dependent, saturable manner. Plasminogen was unaffected 100-fold molar excess angiostatin,...

A unifying feature of many neurodegenerative disorders is the accumulation polyubiquitinated protein inclusions in dystrophic neurons, e.g. containing α-synuclein, which suggestive an insufficient proteasomal activity. We demonstrate that α-synuclein and 20 S proteasome components co-localize Lewy bodies show subunits from particles, contrast to 19 regulatory complex, bind efficiently aggregated filamentous but not monomeric α-synuclein. Proteasome binding insoluble filaments soluble...

Campylobacter jejuni is a gastrointestinal pathogen that able to modify membrane and periplasmic proteins by the N-linked addition of 7-residue glycan at strict attachment motif (D/E)XNX(S/T). Strategies for comprehensive analysis targets glycosylation, however, are hampered resistance glycan-peptide bond enzymatic digestion or β-elimination have previously concentrated on soluble glycoproteins compatible with lectin affinity gel-based approaches. We developed strategies enriching C. HB93-13...

Glycopeptide enrichment is a prerequisite to enable structural characterization of protein glycosylation in glycoproteomics. Here we present an improved method for glycopeptide based on zwitter-ionic hydrophilic interaction chromatography solid phase extraction (ZIC-HILIC SPE) microcolumn format. The involves TFA ion pairing (IP) increase the hydrophilicity difference between glycopeptides and nonglycosylated peptides. Three mobile phases were investigated, i.e., 2% formic acid (defined as...

α-Synuclein has been implicated in the pathogenesis of several neurodegenerative disorders based on direct linking missense mutations α-synuclein to autosomal dominant Parkinson's disease and its presence Lewy-like lesions. To gain insight into functions, we have investigated whether it binds neuronal proteins modulates their functional state. The microtubule-associated protein tau was identified as a ligand by affinity chromatography human brain cytosol. Direct binding assays using...

Abstract Osteopontin (OPN) is a multiphosphorylated glycoprotein found in bone and other normal malignant tissues, as well the physiological fluids urine milk. The present study demonstrates that bovine milk osteopontin phosphorylated at 27 serine residues 1 threonine residue. Phosphoamino acids were identified by combination of amino acid analysis, sequence analysis S‐ethylcysteine‐derivatized phosphopeptides, mass spectrometric analysis. Twenty‐five phosphoserines one phosphothreonine...

Abstract In the small intestine, proglucagon is processed into previously characterized peptide glicentin (proglucagon (PG) 1-69) and two smaller peptides showing about 50% homology with glucagon: glucagon-like peptide-1 -2. It was assumed that sites of post-translational cleavage in intestine precursor were determined by pairs basic amino acid residues flanking peptides. Earlier studies have shown synthetic (GLP-1) synthesized according to proposed structure 71-108 or because residue 108...

Aggregation of the nerve cell protein alpha-synuclein is a characteristic common neurodegenerative alpha-synucleinopathies like Parkinson's disease and Lewy body dementia, it plays direct pathogenic role as demonstrated by early onset diseases caused mis-sense mutations multiplication gene. We investigated existence pro-aggregatory brain proteins whose dysregulation may contribute to progression, we identified brain-specific p25alpha candidate that preferentially binds in its aggregated...

In order to successfully enter the latent stage, Mycobacterium tuberculosis must adapt conditions such as nutrient limitation and hypoxia. vitro models that mimic infection are valuable tools for describing changes in metabolism occur when bacterium exists a non-growing form. We used two complementary proteomic approaches, label-free LC-MS/MS analysis two-dimensional difference gel electrophoresis, determine proteome profile of extracellular proteins from M. cultured under starvation....

Cerebrospinal fluid (CSF) biomarkers for Alzheimer's disease (AD) are increasingly used in research centers, clinical trials, and settings. However, their broad-scale use is hampered by lack of standardization across analytical platforms

Abstract The cannabinoid cannabidiol (CBD) is characterised in this study as a helper compound against resistant bacteria. CBD potentiates the effect of bacitracin (BAC) Gram-positive bacteria ( Staphylococcus species, Listeria monocytogenes , and Enterococcus faecalis ) but appears ineffective Gram-negative reduced MIC value BAC by at least 64-fold combination yielded an FIC index 0.5 or below most tested. Morphological changes S. aureus result included several septa formations during cell...

Summary The proteolytic specificity of chymosin (EC 3.4.23.4) on bovine α s1 -casein at 30°C in phosphate buffer, pH 6·5 and 5·2 the presence 5% (w/v) NaCl was investigated. Peptides (pH 4·6-soluble) were isolated by reversed-phase HPLC identified from their amino acid sequence; identity some peptides confirmed mass spectrometry and/or composition. small produced Arg 1 –Phe 23 , Phe 24 28 –Leu 40 (?), 150 153 156 Tyr 154 –Tyr 159 –Trp 164 Asp 157 165 199 . same peptides, except and,...

Acyl-CoA-binding protein (ACBP) was purified from rat liver. The Mr determined as 9932 +/- 10 by mass spectrometry and calculated 9937.8 the sequence. binds acyl-CoA esters (C8-C16) with high affinity, but unable to bind fatty acids. ACBP found mainly (86%) in soluble fraction, concentration highest liver, 5-6 micrograms/mg of protein. complete primary structure a combination gas-phase Edman degradations spectrometry. Extensive use 252Cf plasma-desorption facilitated identification...

The present paper describes the primary structure, glycosylation and tissue localization of fetal antigen 1 (FA1) isolated from second‐trimester human amniotic fluid. FA1 is a single‐chained, heterogeneous glycoprotein 225–262 amino acid residues. has six well conserved epidermal‐growth‐factor motifs contains up to ten O ‐glycosylation N sites, which are differentially glycosylated. Alignment translated sequences Mus. musculus dlk revealed 86% 99% identity, respectively, 259‐amino‐acid...

NAC, a 35-residue peptide derived from the neuronal protein α-synuclein/NAC precursor, is tightly associated with Aβ fibrils in Alzheimer's disease amyloid, and α-synuclein has recently been shown to bind vitro. We have studied interaction between synucleins, aiming at determining segments that can account for binding, as well identifying possible β-type synuclein. report binds native recombinant α-synuclein, β-synuclein an SDS-sensitive (IC50 approx. 20 μM), determined by chemical...

Protein glycosylation can be vital for changing the function or physiochemical properties of a protein. Abnormal lead to protein malfunction, resulting in severe diseases. Therefore, it is important develop techniques characterization such modifications proteins at sensitivity level comparable with state-of-the-art proteomics. Whereas exist high abundance glycoproteins, no single method presently capable providing information on both site occupancy and glycan structure band excised from an...

Protein and peptide mass analysis amino acid sequencing by spectrometry is widely used for identification annotation of post-translational modifications (PTMs) in proteins. Modification-specific increments, neutral losses or diagnostic fragment ions spectra provide direct evidence the presence modifications, such as phosphorylation, acetylation, methylation glycosylation. However, commonly database search engines are not always practical exhaustive searches multiple concomitant missed...