Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0162871 (abdominal aortic aneurysm)
 8,664 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We examined the synthesis of collagenous proteins by cultured skin fibroblasts taken from 14 patients with an abdominal aortic aneurysm and either an aneurysm at a second site (8 patients) or a first order relative with an abdominal aortic aneurysm (6 patients). Fibroblasts were labeled with [3H] proline and, following pepsin digestion of media proteins, the ratio of type I/III collagen was examined by denaturing polyacrylamide gel electrophoresis (SDS-PAGE). With the exception of two patients, the ratio of type I/III collagen in the media of fibroblasts from aneurysm patients was similar to control values (6 controls). In two of the patients, the type I/III collagen ratio was greater than 3 standard deviations from the mean of both control ratios and those of other aneurysm patients. mRNA levels coding for type III procollagen, however, were normal in both patients. Patient #1 (ME) showed reduced type III procollagen on SDS-PAGE analysis of intracellular proteins. Intracellular and media type III procollagen levels were normal in patient #2 (HR), but media type III collagen was reduced by over 50% after digestion with a combination of trypsin and alpha-chymotrypsin for 5 minutes at 36 degrees C. Control type III collagen was only reduced after digestion at 39 degrees C. These data suggest an altered thermal stability of the type III collagen trimer synthesized by this patient, probably due to a mutation in the amino acid sequence. The data presented in this paper suggest that some forms of common abdominal aortic aneurysms may be caused by mutations in the gene coding for type III procollagen.
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PMID:Abnormalities in the biosynthesis of type III procollagen in cultured skin fibroblasts from two patients with multiple aneurysms. 160 41

Highly purified Golgi membranes were isolated from the scaly green flagellate Scherffelia dubia using osmotic shock for controlled cell rupture, differential centrifugations and a discontinuous sucrose density gradient centrifugation. Three Golgi membrane fractions (based on the distribution of IDPase activity in the gradient) at densities 1.14 g/ml, 1.17 g/ml and 1.20 g/ml were obtained. The specific IDPase activity in these fractions was enriched about 78-fold compared to the crude cell homogenate. The Golgi membrane fractions were further characterized by electron microscopy, SDS-PAGE and lectin blotting. The low density fraction (1.14 g/ml) contained two distinct vesicle populations and scale precursors associated with the outer surface of the larger-size vesicles. The medium density fraction (1.17 g/ml) contained in addition to the larger vesicles, multilamellate vesicles and semicircular cisternae. Finally, in the high density fraction (1.20 g/ml) in addition to small and large vesicles, a tubular membrane reticulum was observed. The three Golgi membrane fractions revealed the same complex overall polypeptide composition when analyzed by SDS-PAGE, but gradual quantitative differences in the polypeptide profile between fractions were observed. The lectins GNA, DSA, and AAA bound to several glycoproteins in all Golgi membrane fractions. Deglycosylation with N-glycosidase F showed that all carbohydrate structures recognized by GNA and DSA, and one recognized by AAA were of the N-glycosidic type indicating the presence of both "high mannose" and "processed" N-glycans in the Golgi apparatus of S. dubia.
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PMID:Isolation and characterization of the Golgi apparatus of a flagellate scaly green alga. 822 93

We have recently purified and partially sequenced a microfibrillar protein from human aortic adventitia (aneurysm-associated antigenic protein, 40 kDa [AAAP-40]) that is immunoreactive with immunoglobulin (IgG) from the wall of abdominal aortic aneurysms (AAAs). It shares motifs with Ig kappa (which may act as a binding site for interaction with integrins), cytomegalovirus (which may be a molecular mimic in the pathogenesis of AAA), and vitronectin and the fibrinogens. A cDNA library was constructed from the aortic adventitia of a AAA. The library was screened with either rabbit anti-vitronectin antibody or rabbit anti-fibrinogen antibody. Positive plaques were purified and expressed in a strain of Escherichia coli. The clone sequences were analyzed. The expressed proteins were separated by SDS/PAGE and the immunoblots were probed with either AAA IgG or anti-human Ig kappa antibody. Experimental cell lines, transfected with the clones (clones 1 and 5), synthesized recombinant proteins (rAAAP-CL1 and rAAAP-CL5), detectable in Western immunoblots with AAA IgG. A prediction of the tertiary structure resembles well-characterized cell adhesion molecules. These findings suggest that there is a novel family of matrix proteins that may use immunoglobulin motifs as binding sites for cellular integrins and that there are matrix proteins in addition to AAAP-40 that may serve as autoantigens in the pathogenesis of AAA disease.
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PMID:Expression of two novel recombinant proteins from aortic adventitia (kappafibs) sharing amino acid sequences with cytomegalovirus. 922 93

Cytochrome c552 is the terminal component of the formate-dependent nitrite reduction pathway of Escherichia coli. In addition to four 'typical' haem-binding motifs, CXXCH-, characteristic of c-type cytochromes, the N-terminal region of NrfA includes a motif, CWSCK. Peptides generated by digesting the cytochrome from wild-type bacteria with cyanogen bromide followed by trypsin were analysed by on-line HPLC MS/MS in parent scanning mode. A strong signal at mass 619, corresponding to haem, was generated by fragmentation of a peptide of mass 1312 that included the sequence CWSCK. Neither this signal nor the haem-containing peptide of mass 1312 was detected in parallel experiments with cytochrome that had been purified from a transformant unable to synthesize NrfE, NrfF and NrfG: this is consistent with our previous report that NrfE and NrfG (but not NrfF) are essential for formate-dependent nitrite reduction. Redox titrations clearly revealed the presence of high and low mid-point potential redox centres. The best fit to the experimental data is for three n=1 components with mid-point redox potentials (pH 7.0) of +45 mV (21% of the total absorbance change), -90 mV (36% of the total) and -210mV (43% of the total). Plasmids in which the lysine codon of the cysteine-lysine motif, AAA, was changed to the histidine codon CAT (to create a fifth 'typical' haem c-binding motif), or to the isoleucine and leucine codons, ATT and CTT, were unable to transform a Nrf deletion mutant to Nrf+ or to restore formate-dependent nitrite reduction to the transformants. The presence of a 50 kDa periplasmic c-type cytochrome was confirmed by staining proteins separated by SDS-PAGE for covalently bound haem, but the methyl-viologen-dependent nitrite reductase activities associated with the mutated proteins, although still detectable, were far lower than that of the native protein. The combined data establish not only that there is a haem group bound covalently to the cysteine-lysine motif of cytochrome c552 but also that one or more products of the last three genes of the nrf operon are essential for the haem ligation to this motif.
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PMID:Involvement of products of the nrfEFG genes in the covalent attachment of haem c to a novel cysteine-lysine motif in the cytochrome c552 nitrite reductase from Escherichia coli. 959 8

The pcd gene from Flavobacterium lutescens IFO3084 encoding Delta'-piperideine-6-carboxylate dehydrogenase (PCD) was cloned, sequenced, and expressed in Escherichia coli. The deduced amino acid sequence of PCD from F. lutescens IFO3084 showed strong similarity to that from Streptomyces clavuligerus. The molecular mass of the recombinant PCD was estimated to be approximately 58,000 Da by SDS-PAGE and native PAGE, which indicated that the enzyme molecule is a monomer. The in vitro analysis of L-alpha-aminoadipic acid (L-AAA) production showed that L-AAA is synthesized from L-lysine in two steps catalyzed by L-lysine 6-aminotransferase (LAT) and PCD from F. lutescens IFO3084.
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PMID:Cloning and characterization of pcd encoding delta'-piperideine-6-carboxylate dehydrogenase from flavobacterium lutescens IFO3084. 1109 40

TolAI--II--beta-lactamase, a fusion protein consisting of the inner membrane and transperiplasmic domains of TolA followed by TEM--beta-lactamase associated with the inner membrane but remained confined to the cytoplasm when expressed at high level in Escherichia coli. Although the fusion protein was resistant to proteolysis in vivo, it was hydrolyzed during preparative SDS-polyacrylamide electrophoresis and when insoluble cellular fractions unfolded with 5 M urea were subjected to microdialysis. Inhibitor profiling studies revealed that both a metallo- and serine protease were involved in TolAI--II--beta-lactamase degradation under denaturing conditions. The in vitro degradation rates of the fusion protein were not affected when insoluble fractions were harvested from a strain lacking protease IV, but were significantly reduced when microdialysis experiments were conducted with material isolated from an isogenic ftsH1 mutant. Adenine nucleotides were not required for degradation, and ATP supplementation did not accelerate the apparent rate of TolAI--II--beta-lactamase hydrolysis under denaturing conditions. Our results indicate that the metalloprotease active site of FtsH remains functional in the presence of 3--5 M urea and suggest that the ATPase and proteolytic activities of FtsH can be uncoupled if the substrate is sufficiently unstructured. Thus, a key role of the FtsH AAA module appears to be the net unfolding of bound substrates so that they can be efficiently engaged by the protease active site.
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PMID:Escherichia coli FtsH (HflB) degrades a membrane-associated TolAI-II-beta-lactamase fusion protein under highly denaturing conditions. 1123 95

The single nucleotide polymorphism (SNP) of aldehyde dehydrogenase-2 (ALDH2) codon 487, GAA (Glu) or AAA (Lys), was examined using green fluorescent protein (GFP)-display, an electrophoretic detection method for single amino acid changes. Although no shift in migration between the GFP-ALDH (Glu487) and GFP-ALDH (Lys487) fusion proteins was observed on SDS/urea gel, the two migrated to different positions when tagged with Asp. The SNP analysis was performed with GFP-ALDH-Asp3, and GFP-ALDH-Asp3 constructed from donors having the codon GAA/GAA, GAA/AAA or AAA/AAA was detected as different patterns as expected. GFP-display is potentially a unique method in SNP analysis, which does not require any special equipment or chemicals.
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PMID:A new method for detecting single nucleotide polymorphism using GFP-display. 1523 11

The serine/threonine kinase Akt is a key mediator of cell survival and growth, but its precise mechanism of action, and more specifically, the nature of its signaling partners largely remain to be elucidated. We show, using a proteomics-based approach, that the valosin-containing protein (VCP), a member of the AAA (ATPases associated with a variety of cellular activities) family, is a target of Akt signaling. SDS-PAGE of Akt co-immunoprecipitated proteins obtained from MCF-7 breast cancer cells revealed the increase of a 97-kDa band under Akt activation. Mass spectrometry analysis allowed the identification of VCP, and we have shown a serine/threonine phosphorylation on an Akt consensus site upon activation by growth factors. Site-directed mutagenesis identified Ser-351, Ser-745, and Ser-747 as Akt phosphorylation sites on VCP. Confocal microscopy indicated a co-localization between Akt and VCP upon Akt stimulation. Interestingly, small interfering RNA against VCP induced an inhibition of the growth factor-induced activation of NF-kappaB and a potent pro-apoptotic effect. Together, these data identify VCP as an essential target of Akt signaling.
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PMID:The valosin-containing protein (VCP) is a target of Akt signaling required for cell survival. 1655 32

An AAA-ATPase (ATPases Associated with a Variety of Cellular Activities) localized to the plasma membrane of soybean (Glycine max) was isolated, partially sequenced and cloned (SBPM AAA-ATPase). The protein with an apparent monomer molecular mass of about 97 kDa was isolated using a combination of anion exchange, preparative SDS-PAGE, reverse phase HPLC, and ATP affinity chromatography. The cDNA for the full-length SBPM AAA-ATPase was cloned by screening an expression library using an antibody against the highly conserved Walker B AAA-ATP-binding motif. Northern blot analysis detected one transcript of approximately 2700 bp. The full-length cDNA sequence was that previously obtained (GenBank Database; U20213) encoding a protein with two copies of the conserved AAA-ATP-binding motif and regions of sequence homology with other AAA-ATPases. Electron microscopic preparations of the recombinant SBPM AAA-ATPase revealed hexamers typically formed by these proteins. The cloned and expressed protein was identical to the protein isolated from the soybean plasma membrane as confirmed using antisera raised to a non-conserved region of the derived protein sequence and by N-terminal sequencing of peptides derived from the isolated protein.
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PMID:A plasma membrane-associated AAA-ATPase from Glycine max. 1737 43

Cysteine dithiol/disulphide exchange forms the molecular basis for regulation of a wide variety of enzymatic activities and for transduction of cellular signals. Thus, the search for proteins with reactive, accessible cysteines is expected to contribute to the unravelling of new molecular mechanisms for enzyme regulation and signal transduction. Several methods have been designed for this purpose taking advantage of the interactions between thioredoxins and their protein substrates. Thioredoxins comprise a family of redox-active enzymes, which catalyse reduction of protein disulphides and sulphenic acids. Due to the inherent practical difficulties associated with studies of membrane proteins these have been largely overlooked in the many proteomic studies of thioredoxin-interacting proteins. In the present work, we have developed a procedure to isolate membrane proteins interacting with thioredoxin by binding in situ to a monocysteinic His-tagged thioredoxin added directly to the intact membranes. Following fractionation and solubilisation of the membranes, thioredoxin target proteins were isolated by Ni-affinity chromatography and 2-DE SDS-PAGE under nonreducing/reducing conditions. Applying this method to total membranes, including thylakoid and plasma membranes, from the cyanobacterium Synechocystis sp. PCC 6803 we have identified 50 thioredoxin-interacting proteins. Among the 38 newly identified thioredoxin targets are the ATP-binding subunits of several transporters and members of the AAA-family of ATPases.
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PMID:Membrane proteins from the cyanobacterium Synechocystis sp. PCC 6803 interacting with thioredoxin. 1792 17


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