Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.3.3.1 (citrate synthase)
 4,488 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

DNA sequences from specific genes, amplified by the polymerase chain reaction technique, were used as substrata for nonisotopic restriction endonuclease fragment length polymorphism differentiation of rickettsial species and genotypes. The products amplified using a single pair of oligonucleotide primers (derived from a rickettsial citrate synthase gene sequence) and cleaved with restriction endonucleases were used to differentiate almost all recognized species of rickettsiae. A second set of primers was used for differentiation of all recognized species of closely related spotted fever group rickettsiae. The procedure circumvents many technical obstacles previously associated with identification of rickettsial species. Multiple amplified DNA digest patterns were used to estimate the intraspecies nucleotide sequence divergence for the genes coding for rickettsial citrate synthase and a large antigen-coding gene of the spotted fever group rickettsiae. The estimated relationships deduced from these genotypic data correlate reasonably well with established rickettsial taxonomic schemes.
 ...
PMID:Genotypic identification of rickettsiae and estimation of intraspecies sequence divergence for portions of two rickettsial genes. 167 56

Among 56 patients with mitochondrial myopathies or cytopathies, 19 had large-scale deletions of mitochondrial DNA (mtDNA). Consistent with previous observations, all 19 had progressive external ophthalmoplegia and 12 had complete or partial Kearns-Sayre syndrome. One of two patients in whom mitochondrial rather than whole muscle DNA was analyzed had multiple populations of deleted mtDNA (dmtDNA). In all patients, the length of dmtDNA was inversely related to age of onset, but was not related to multiplicity of organ involvement. Patients with greater than 50% dmtDNA tended to have an earlier onset of symptoms and a higher proportion of ragged-red fibers and cytochrome c oxidase (CCO)-negative fibers than patients with less than 50% dmtDNA, but these differences did not reach statistical significance. In some patients, CCO-negative fibers were more abundant than ragged-red fibers, indicating that the distribution of abnormal mitochondria can be more widespread than suggested by the frequency of ragged-red fibers. In biochemical assays, citrate synthase activity was a better reference for detecting defects in the respiratory complexes than the wet weight of muscle. Using this reference, 10 of 14 patients had one or more respiratory complex defects, and 74% of the observed defects could be correlated with an appropriate mtDNA deletion.
 ...
PMID:Mitochondrial DNA deletions in mitochondrial cytopathies: observations in 19 patients. 168 53

Skeletal muscle grafts performed with neurovascular repair are used extensively in clinical situations. However, most controlled experimental studies on the efficacy of such grafts have been conducted on muscles with a relatively small mass and over a limited recovery period. Therefore, selected cellular and matrix component properties of the comparatively large dog gracilis muscle (75 g) were studied 9-12 mo after orthotopic neurovascular grafting. The grafted muscle wet weights were 71% of the contralateral control (sham-operated) muscles. In addition, the concentrations of noncollagenous protein (13%), DNA (28%), and RNA (34%) were significantly reduced in the grafts. However, the concentration of collagen was significantly higher (41%) in the grafts. In this regard, the type III collagen phenotype showed the greatest relative increase. There was no difference between the grafted and control proteoglycan concentration. The metabolic profiles of the grafted muscles were significantly different from control. The activities of myofibrillar adenosinetriphosphatase (34%) and alpha-glycerophosphate dehydrogenase (25%) were reduced, whereas citrate synthase remained unchanged. These data suggest that recovery of up to 1 yr was insufficient for the normalization of several connective tissue matrix components and biochemical properties of the grafts.
 ...
PMID:Incomplete normalization of dog gracilis muscle grafts with neurovascular repair despite long-term recovery. 169 Jun 97

1. Biopsies of the extensor hallucis longus (EHL) and gastrocnemius (G) muscles of four captive black bears (Ursus americanus) were obtained prior to denning (PRE), during denning (DEN) and following the Spring arousal (POST). 2. Glycogen, triglyceride and protein concentrations did not differ significantly between the three groups. Likewise, the activity of citrate synthase, a mitochondrial oxidative enzyme, was not significantly different between the three groups. 3. DNA concentrations in DEN samples increased 30% compared to other groups while RNA concentrations were significantly elevated in POST samples. The RNA/DNA ratios were significantly depressed during DEN. 4. These results suggest a degree of muscle atrophy during DEN, with the potential for an increased capacity for muscle protein synthesis following the Spring arousal.
 ...
PMID:Biochemical changes in skeletal muscles of denning bears (Ursus americanus). 172 46

The identification of apparently fastidious microorganisms is often problematic. DNA from a rickettsia-like agent (called the ELB agent) present in cat fleas could be amplified by PCR with conserved primers derived from rickettsial 17-kDa common protein antigen and citrate synthase genes but not spotted fever group 190-kDa antigen gene. Alu I sites in both the 17-kDa and citrate synthase PCR products obtained with the rickettsia-like agent and Rickettsia typhi were different even though both agents reacted with monoclonal antibodies previously thought specific for R. typhi. The DNA sequence of a portion of the 17-kDa PCR product of the rickettsia-like agent differed significantly from all known rickettsial sequences and resembled the 17-kDa sequences of typhus more than spotted fever group rickettsiae. The rare stable transovarial maintenance of this rickettsia in cat fleas has important implications for the disease potential of cat fleas.
 ...
PMID:Genetic characterization and transovarial transmission of a typhus-like rickettsia found in cat fleas. 172 13

1. Morphological, biochemical and metabolic characteristics of hindlimb muscles from summer-active (SA), winter-active (WA) and hibernating (H) golden-mantled ground squirrels (Spermophilus lateralis) were examined to identify alterations resulting from seasonal periods of inactivity. 2. Cross-sectional areas of fibers from the soleus were reduced in both WA and H, although only significantly (P less than 0.05) in WA. Fibers in the EDL exhibited significant reductions in cross-sectional areas in both H and WA groups. Muscle fiber and capillary densities were altered in quantitative agreement with changes in cross-sectional areas. 3. Protein content was reduced 20% (P less than 0.05) in EDL from H and WA groups, but reductions (10%) in the soleus were not statistically significant. RNA content in WA and H groups was significantly decreased in soleus (20%) and EDL (35%) compared with SA, but DNA content was unchanged. 4. In the plantaris, triglyceride content was unchanged, but citrate synthase activity in H (210 +/- 13 mumol min-1 g-1) was significantly greater than in SA (177 +/- 10). In contrast, LDH activity in H was reduced by 25% (P less than 0.05) compared with SA. 5. These results demonstrate atrophic effects associated with seasonal inactivity in hibernating ground squirrels, but suggest the existence of natural mechanisms which limit the response.
 ...
PMID:Morphometric and metabolic indices of disuse in muscles of hibernating ground squirrels. 179 Jun 75

A Mycobacterium smegmatis PstI library was constructed by cloning these fragments downstream from the lac promoter of the expression vector pHG171. Three identically sized clones were isolated by complementation of an Escherichia coli strain (chi 2338) deficient in citrate synthase. One insert (pBL265) was used in hybridization experiments with DNA from E. coli and M. smegmatis and it was demonstrated that the clones were indeed from M. smegmatis. The transcription of the M. smegmatis citrate synthase gene in E. coli relied upon the lac promoter. In translation experiments performed in vitro pBL265 gave rise to a novel protein of about 42 kDa. This band was not seen in 'opposite-orientation' subclones. Various subclones in which the 5'-end was shortened nevertheless complement E. coli chi 2338 and produce the 42 kDa protein. This demonstrates that the M. smegmatis citrate synthase gene uses its own ribosome-binding site in E. coli. The relevant 1.8 kb of the 2.8 kb insert was sequenced. A consensus E. coli ribosome-binding site was found centred precisely 10 bp upstream of the methionine codon. Other interesting features revealed by the sequence are discussed. Citrate synthase activity was assayed in vitro and the mycobacterial enzyme was found to be similar to those of the Gram-positive bacteria.
 ...
PMID:Citrate synthase from Mycobacterium smegmatis. Cloning, sequence determination and expression in Escherichia coli. 188 31

Muscle biopsy specimens were obtained from 48 human immunodeficiency virus-infected patients suffering from various neuromuscular symptoms. Microscopic examination by conventional and electron microscopy revealed a characteristic structural myopathy associated with mitochondrial changes in 13 patients, all of whom had received long-term zidovudine therapy. The mean cumulative dose they had received (498 +/- 145 gm) was significantly higher than that of the other 14 zidovudine recipients of the study. They suffered from a progressive, usually painful, proximal myopathy with pronounced wasting, normal-to-moderately elevated creatine kinase levels, and a myopathic electromyographic pattern. The condition usually improved after withdrawal of the drug. Assay of mitochondrial enzymes, including succinate-cytochrome c reductase, cytochrome c oxidase, and citrate synthase, showed a decline in respiratory chain capacity. Southern blot analysis of mitochondrial DNA showed no abnormality. It is likely that mitochondrial dysfunction, probably resulting from drug-induced inhibition of the mitochondrial DNA polymerase, is implicated in the pathogenesis of this complication of zidovudine therapy.
 ...
PMID:Zidovudine myopathy: a distinctive disorder associated with mitochondrial dysfunction. 189 64

Peroxisomal (nonmitochondrial) citrate synthase (CS2) has been purified from a Saccharomyces cerevisiae strain in which the gene for the mitochondrial citrate synthase (CS1) had been disrupted and no CS1 protein is produced. The enzyme, CS2, the sequence of which had been previously determined from its DNA, behaved differently from CS1 in its purification, kinetics, stability, and binding to the inner surface of mitochondrial inner membranes.
 ...
PMID:Studies on yeast peroxisomal citrate synthase. 189 42

We have examined the effects of perturbation of mitochondrial function on expression of two nuclear genes encoding the mitochondrial and peroxisomal forms of citrate synthase in Saccharomyces cerevisiae, CIT1 and CIT2. CIT2 expression was as much as 30-fold higher in [rho0] petites, than in isochromosomal [rho+] cells, whereas CIT1 expression was slightly down regulated in [rho0] cells. CIT2 expression was also increased in [rho+] cells by inhibition of respiration with antimycin A or in [rho+] cells containing a disruption of the CIT1 gene. These effects were additive, and together they approached the level of CIT2 expression seen in [rho0] cells. Experiments using heterologous gene fusions showed that all of the effects leading to increased expression of CIT2 were transcriptionally controlled through 5'-flanking CIT2 DNA sequences. Analysis of [rho+] and [rho0] cells containing disruptions of CIT1 and CIT2, singly and in combination, showed that the peroxisomal citrate synthase could partially spare the mitochondrial isoform for growth yield in [rho+] but not in [rho0] cells. These studies suggest a physiological role for increased expression of CIT2 in cells with altered mitochondrial function. They also provide additional evidence for a retrograde path of communication from mitochondria to the nucleus in yeast cells.
 ...
PMID:Intramitochondrial functions regulate nonmitochondrial citrate synthase (CIT2) expression in Saccharomyces cerevisiae. 198 32


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>