Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0038187 (starvation)
 24,951 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Glypicans are a group of membrane-bound heparan sulfate proteoglycans (HSPG) that are tissue specific and developmentally regulated. Transcripts for avian glypican are found in endocardial cushions, limb buds, somites and forebrain of early chick embryos. Since avian glypican is not well characterized, the cellular localization, regulation of expression, and possible function during cardiac development have been studied. A polyclonal antibody was raised against a 20-amino acid peptide corresponding to an antigenic sequence within avian glypican core protein. The antibody recognized the expressed core protein in bacterial lysates and the endogenous HSPG in the proteoglycan fraction from chick forebrain. Immunolocalization studies indicated that the core protein is associated with cell membranes. The level of mRNA for avian glypican in MEQC (myc embryonic quail cardiomyocytes) grown in medium containing 10% fetal calf serum was compared to the message levels in cells grown without serum for 3 days. By Northern analysis, glypican transcripts were increased markedly after serum starvation. Up-regulation of glypican transcripts by serum withdrawal was partially prevented by addition of TGFbeta-1 and bFGF, suggesting that these growth factors may regulate its expression. MEQC cells deprived of serum migrated into clumps that could be blocked by an antisense OND (oligodeoxynucleotide) to the mRNA encoding the avian glypican. The same antisense OND inhibited the migration of endothelial cells from chick tubular heart explants over the surface of collagen gels. These results indicate that avian glypican may play a role in cell migration during development of endocardial cushions.
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PMID:Structure, regulation and function of avian glypican. 951 30

Pseudomonas aeruginosa PAO1 grew in defined synthetic medium with any of a broad variety of single sulfur sources, including sulfate, cysteine, thiocyanate, alkanesulfonates, organosulfate esters and methionine, but not with aromatic sulfonates, thiophenols or organothiocyanates or isothiocyanates. During growth with any of these compounds except sulfate, cysteine or thiocyanate, a set of 10 sulfate starvation-induced (SSI) proteins was strongly up-regulated, as observed by two-dimensional protein electrophoresis of total cell extracts. A comparable level of up-regulation was found for the hydrolytic enzyme arylsulfatase, which has previously been used as a marker enzyme for the sulfate starvation response. One of the SSI proteins was identified by N-terminal sequencing as a high-affinity periplasmic sulfate-binding protein, and another was related to thiol-specific antioxidants, but the N-terminal sequences of the other SSI proteins revealed no similarity to N-termini of proteins of known function, and they probably represent uncharacterized enzymes involved in sulfur scavenging when preferred sulfur sources are absent. To study the role that cysteine biosynthetic intermediates play in the synthesis of these proteins in vivo, we isolated mini-Tn5 transposon mutants of P. aeruginosa with insertions in the cysN and cysI genes, which encode subunits of ATP-sulfurylase and sulfite reductase, respectively. These two genes were cloned and sequenced. cysI showed high similarity to the cognate gene in Escherichia coli, whereas cysN encoded a 69.3 kDa protein with two domains corresponding to the E. coli CysN and CysC proteins. Sulfate no longer repressed synthesis of the SSI proteins in cysN mutants, but repression was restored by sulfite; in the cysI mutant, sulfate, sulfite and sulfide all led to repression of SSI protein synthesis. This suggests that there are at least two independent corepressors of the sulfate starvation response in this species.
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PMID:Regulation of the sulfate starvation response in Pseudomonas aeruginosa: role of cysteine biosynthetic intermediates. 961 12

Bacteroides fragilis strains isolated from different sources, i.e. 1 strain (AA1) from an aquatic environment, 1 strain from normal flora (118310) and the type strain (ATCC 25285) originally isolated from clinical material, were analysed for both cell envelope proteins composition and surviving under oxidative stress starvation. All strains examined showed a similar survival response when cultured in drinking water with a ten-fold decrease in viable counts per day during the 7 days of analysis. The outer membrane protein (OMP) profiles of all strains were quite similar during the stress period as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). However, the periplasmic proteins of the strain 118310 showed two protein bands at 48 and 58 kDa, respectively, that were absent in the strains AA1 and ATCC 25285 during the incubation period in potable water. Whole cells and periplasmic 35S-labelled proteins from bacteria cultured in drinking water showed a significant increase in proteins at 16, 18, 24, 26, 35, 48, and 58 kDa and 18, 22, 24, 48, 58, and 70 kDa, respectively, in all strains when compared to cells grown in BHI-PRAS media as detected by autoradiography following SDS-PAGE. These data suggest that B. fragilis may have a synthesis mechanism that allows them to adapt to adverse environments.
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PMID:Influence of stress conditions on Bacteroides fragilis survival and protein profiles. 963 69

Three polymorphic subtypes of erythrocyte histone H1 (H1.a, H1.b, and H1.z) were analyzed using a sodium dodecyl sulfate polyacrylamide gel in quail populations divergently selected for a high (line 1) or low (line 2) reduction in body mass following temporary food withdrawal. Both H1.b and H1.z histone alleles were found to be differently distributed in these populations during the selection period. The frequency of b1 in line 2 was approximately 1.9-2.8 times lower than in line 1 and approached the values in line 1 when the selection was suspended. Similarly, the frequency of allele z2 at locus H1.z increased significantly (about 1.6-2.3 times) in line 2 during selection and returned to the initial values when selection was stopped. On the other hand, allele a0 at locus H1.a was kept at relatively low levels (usually below 0.05) in both lines during selection. At that time its level was approximately three to four times lower than in a random mating control population. When selection was suspended, the frequency of a0 in line 1 increased significantly, approaching the values in the control line, and remained essentially unchanged in line 2. Thus, all three polymorphic histone H1 loci in quail responded through changes in allele frequencies to the breeding selection, which was directed at the amount of body weight loss upon transient starvation. It seems that either H1 histone locus could be linked to loci controlling the rate of body weight reduction following starvation or weight loss during fasting might be influenced by a panel of H1 histone alleles that can contribute to functional differences in avian chromatin.
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PMID:Distribution of allelic forms of erythrocyte H1 histones in Japanese quail populations divergently selected for amount of weight loss after transient starvation. 967 72

Organosulfonates are widespread compounds, be they natural products of low or high molecular weight, or xenobiotics. Many commonly found compounds are subject to desulfonation, even if it is not certain whether all the corresponding enzymes are widely expressed in nature. Sulfonates require transport systems to cross the cell membrane, but few physiological data and no biochemical data on this topic are available, though the sequences of some of the appropriate genes are known. Desulfonative enzymes in aerobic bacteria are generally regulated by induction, if the sulfonate is serving as a carbon and energy source, or by a global network for sulfur scavenging (sulfate-starvation-induced (SSI) stimulon) if the sulfonate is serving as a source of sulfur. It is unclear whether an SSI regulation is found in anaerobes. The anaerobic bacteria examined can express the degradative enzymes constitutively, if the sulfonate is being utilized as a carbon source, but enzyme induction has also been observed. At least three general mechanisms of desulfonation are recognisable or postulated in the aerobic catabolism of sulfonates: (1) activate the carbon neighboring the C-SO3- bond and release of sulfite assisted by a thiamine pyrophosphate cofactor; (2) destabilize the C-SO3- bond by addition of an oxygen atom to the same carbon, usually directly by oxygenation, and loss of the good leaving group, sulfite; (3) an unidentified, formally reductive reaction. Under SSIS control, different variants of mechanism (2) can be seen. Catabolism of sulfonates by anaerobes was discovered recently, and the degradation of taurine involves mechanism (1). When anaerobes assimilate sulfonate sulfur, there is one common, unknown mechanism to desulfonate the inert aromatic compounds and another to desulfonate inert aliphatic compounds; taurine seems to be desulfonated by mechanism (1).
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PMID:Microbial desulfonation. 999 Jul 24

When Pseudomonas aeruginosa is grown with organosulfur compounds as sulfur sources, it synthesizes a set of proteins whose synthesis is repressed in the presence of sulfate, cysteine, or thiocyanate (so-called sulfate starvation-induced proteins). The gene encoding one of these proteins, PA13, was isolated from a cosmid library of P. aeruginosa PAO1 and sequenced. It encoded a 381-amino-acid protein that was related to several reduced flavin mononucleotide (FMNH2)-dependent monooxygenases, and it was the second in an operon of three genes, which we have named msuEDC. The MsuD protein catalyzed the desulfonation of alkanesulfonates, requiring oxygen and FMNH2 for the reaction, and showed highest activity with methanesulfonate. MsuE was an NADH-dependent flavin mononucleotide (FMN) reductase, which provided reduced FMN for the MsuD enzyme. Expression of the msu operon was analyzed with a transcriptional msuD::xylE fusion and was found to be repressed in the presence of sulfate, sulfite, sulfide, or cysteine and derepressed during growth with methionine or alkanesulfonates. Growth with methanesulfonate required an intact cysB gene, and the msu operon is therefore part of the cys regulon, since sulfite utilization was found to be CysB independent in this species. Measurements of msuD::xylE expression in cysN and cysI genetic backgrounds showed that sulfate, sulfite, and sulfide or cysteine play independent roles in negatively regulating msu expression, and sulfonate utilization therefore appears to be tightly regulated.
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PMID:A novel reduced flavin mononucleotide-dependent methanesulfonate sulfonatase encoded by the sulfur-regulated msu operon of Pseudomonas aeruginosa. 1004 77

Total level of O-acetyl-L-serine(thiol)lyase (OASTL) activity observed in Monoraphidium braunii fed-repleted cells decreases up to 40% after 24 h the carbon source was removed from the culture; however, no significant change in the activity is observed in N-starved cells. On the other hand, sulfur starvation induces OASTL activity in M. braunii, which may increase 2.5-fold after 36 h. Normal intracellular level of the activity is restored when a sulfur source, such as sulfate, sulfite, L-cysteine, L-methionine or glutathione is added to the culture. The induction of the OASTL activity requires de novo synthesis of protein, and thus the presence in the culture of adequate carbon and nitrogen sources. The OASTL isoenzymes from M. braunii cells are differently affected by S-starvation.
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PMID:Regulation of the O-acetyl-L-serine(thiol)lyase activity in Monoraphidium braunii. 1021 10

Sulfate uptake and ATP sulfurylase activity in the roots of Arabidopsis thaliana and Brassica napus were enhanced by S deprivation and reduced following resupply of SO4(2-). Similar responses occurred in split-root experiments where only a portion of the root system was S-deprived, suggesting that the regulation involves inter-organ signaling. Phloem-translocated glutathione (GSH) was identified as the likely transducing molecule responsible for regulating SO4(2-) uptake rate and ATP sulfurylase activity in roots. The regulatory role of GSH was confirmed by the finding that ATP sulfurylase activity was inhibited by supplying Cys except in the presence of buthionine sulfoximine, an inhibitor of GSH synthesis. In direct and remote (split-root) exposures, levels of protein detected by antibodies against the Arabidopsis APS3 ATP sulfurylase increased in the roots of A. thaliana and B. napus during S starvation, decreased after SO4(2-) restoration, and declined after feeding GSH. RNA blot analysis revealed that the transcript level of APS1, which codes for ATP sulfurylase, was reduced by direct and remote GSH treatments. The abundance of AST68 (a gene encoding an SO4(2-) transporter) was similarly affected by altered sulfur status. This report presents the first evidence for the regulation of root genes involved in nutrient acquisition and assimilation by a signal that is translocated from shoot to root.
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PMID:Inter-organ signaling in plants: regulation of ATP sulfurylase and sulfate transporter genes expression in roots mediated by phloem-translocated compound. 1034 46

The Escherichia coli ssuEADCB gene cluster is required for the utilization of alkanesulfonates as sulfur sources, and is expressed under conditions of sulfate or cysteine starvation. The SsuD and SsuE proteins were overexpressed and characterized. SsuE was purified to homogeneity as an N-terminal histidine-tagged fusion protein. Native SsuE was a homodimeric enzyme of M(r) 58,400, which catalyzed an NAD(P)H-dependent reduction of FMN, but it was also able to reduce FAD or riboflavin. The SsuD protein was purified to >98% purity using cation exchange, anion exchange, and hydrophobic interaction chromatography. The pure enzyme catalyzed the conversion of pentanesulfonic acid to sulfite and pentaldehyde and was able to desulfonate a wide range of sulfonated substrates including C-2 to C-10 unsubstituted linear alkanesulfonates, substituted ethanesulfonic acids and sulfonated buffers. SsuD catalysis was absolutely dependent on FMNH(2) and oxygen, and was maximal for SsuE/SsuD molar ratios of 2.1 to 4.2 in 10 mM Tris-HCl, pH 9.1. Native SsuD was a homotetrameric enzyme of M(r) 181,000. These results demonstrate that SsuD is a broad range FMNH(2)-dependent monooxygenase catalyzing the oxygenolytic conversion of alkanesulfonates to sulfite and the corresponding aldehydes. SsuE is the FMN reducing enzyme providing SsuD with FMNH(2).
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PMID:Characterization of a two-component alkanesulfonate monooxygenase from Escherichia coli. 1048 Aug 65

In industrial fermentations, Penicillium chrysogenum uses sulfate as the source of sulfur for the biosynthesis of penicillin. By a PCR-based approach, two genes, sutA and sutB, whose encoded products belong to the SulP superfamily of sulfate permeases were isolated. Transformation of a sulfate uptake-negative sB3 mutant of Aspergillus nidulans with the sutB gene completely restored sulfate uptake activity. The sutA gene did not complement the A. nidulans sB3 mutation, even when expressed under control of the sutB promoter. Expression of both sutA and sutB in P. chrysogenum is induced by growth under sulfur starvation conditions. However, sutA is expressed to a much lower level than is sutB. Disruption of sutB resulted in a loss of sulfate uptake ability. Overall, the results show that SutB is the major sulfate permease involved in sulfate uptake by P. chrysogenum.
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PMID:Sulfate transport in Penicillium chrysogenum: cloning and characterization of the sutA and sutB genes. 1057 25


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