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C C Rider

Publications and source records attributed to C C Rider.

46 records · Page 3Linked to original sources
PubMed1983

Multiple chromatographic forms of ATP citrate lyase from rat liver.

ATP citrate lyase is shown to exist as multiple forms in extracts of rat liver. DEAE-Sephadex ion-exchange chromatography of liver supernatants reveals two peaks of activity. A minor, basic, component, comprising 14% of the recovered activity, is eluted without retention, whereas the major, acidic, form is eluted by a KCl gradient. Gel filtration of similar extracts shows the presence of a high-Mr form of ATP citrate lyase (Mr around 10(7) in addition to the tetrameric enzyme (Mr 4.1 X 10(5). This associated state, which represents 10% of the total activity, is unstable, breaking down to the tetramer, and appears to be disrupted by Mg2+. The basic form changes in the partially purified state to give the acidic form. Most of the high-Mr enzyme is acidic in nature. No evidence could be found for an association of the enzyme with mitochondrial or microsomal membranes. ATP citrate lyase from rat brain also shows two peaks of activity on DEAE-Sephadex ion-exchange chromatography, but the activity is distributed between the peaks in almost equal proportions. However, only the tetrameric enzyme was observed on gel filtration.

ATP Citrate (pro-S)-Lyase↗
PubMed1976

Enolase isoenzymes. III. Chromatographic and immunological characteristics of rat brain enolase.

1. The chromatography of rat brain enolase (2-phospho-D-glycerate hydrolyase, EC 4.2.1.11) reveals three distinet components. One of these appears to be isoenzyme 1 (alpha alpha) but isoenzymes 2 (alpha beta) and 3 (beta beta) are absent. 2. The most acidic form of brain enolase was partially purified and an antiserum raised against it in the chicken. 3. a combination of chromatographic and immunological studies showed that a third type of subunit (gamma) is present in the brain giving rise to two further isoenzymes (alpha gamma and gamma gamma). 4. Developmental studies on the brain enzyme show an increase in total enolase activity from foetal life to maturity and a concurrent rise in the proportion of brain specific dimers. 5. It is therefore concluded that there are three genetic loci alpha, beta and gamma, coding for the enolase isoenzymes of rat tissues.

Aging↗
PubMed1976

Total and immunologically reacting muscle enolase in blood serum of Duchenne muscular dystrophy patients and carriers.

All of 12 patients with Duchenne muscular dystrophy manifested raised activity of serum enolase but only 10 showed elevation of immunologically reacting muscle enolase (IRM-enolase). Total enolase was raised in 4 of 12 mothers and one of 8 sisters of the affected subjects but IRM-enolase was elevated in only one mother. These results are consistent with the view that enolase, unlike creatine phosphokinase which showed much more pronounced increase in the serum of patients and their female relatives, is associated with a structural component of the muscle cell distinct from the presumed site of molecular abnormality in this disease.

Adult↗
PubMed1976

Serum enolase and pyruvate kinase activities in the diagnosis of myocardial infarction.

Sequential determinations of serum enolase and pyruvate kinase (PK) activities were carried out in addition to routine enzyme assays on 191 patients admitted to a coronary care unit. The upper reference values established in 61 healthy laboratory staff members were 21 U/1 for enolase and 76 U/1 for PK. Of 99 patients with a confirmed diagnosis of myocardial infarction (MI), 97 manifested raised serum enolase during the period of observation; 85 of these patients had raised serum PK. The incidence of raised values for serum PK among patients considered not to have sustained infarction was similar to that shown by the routine enzymes, but serum enolase activity was much more frequently raised in these patients. The time-course of elevation of serum enolase and also that of PK are discussed in relation to the changes in other serum enzymes routinely measured for MI.

Clinical Enzyme Tests↗
PubMed1975

Immunological determination of muscle-type enolase in the serum as a diagnostic test for myocardial infarction.

An antiserum raised in the chicken against purified rat skeletal muscle enolase neutralized 86% of the enolase activity of human heart muscle and 8.7% +/- 4.8% (mean +/- S.D.) of the enolase activity in normal human serum. The fraction of enolase inhibited by the antiserum, designated as 'immunologically reacting muscle enolase', promptly rose after myocardial infarction in the serum of affected subjects, reaching peak values in excess of 40% in all but one of 23 subjects. Only one subject with ischaemic heart disease, but without infarction, and 2 with miscellaneous conditions, among 117 such patients tested, yielded comparable values. The test appears to be highly specific for myocardial infarction when muscle disease can be excluded and would not be difficult to introduce as a laboratory routine.

Diagnosis, Differential↗
PubMed1975

Enolase isoenzymes. II. Hybridization studies, developmental and phylogenetic aspects.

1. Hybridization studies have been carried out in vitro using mixtures of partially purified isoenzymes 1 and 3 of rat enolase (2-phospho-D-glycerate hydrolyase, EC 4.1.1.11). Immunological methods were used to demonstrate the formation of the hybrid. 2. Immunological analysis of the elution peaks from QAE-Sephadex chromatography of heart enolase indicates the occurrence in vivo of the hybrid enolase 2. 3. Developmental changes in the proportions of isoenzymes 1, 2 and 3 in heart and skeletal muscle of rat have been studied quantitatively. In both tissues isoenzyme 1 predominates in the foetus, but is partially replaced by 2 and 3 in adult heart and completely by 3 in the adult muscle. 4. Evidence is given of the binomial distribution of the proportions of the three isoenzymes in the developing heart. 5. Phylogenetic studies of the immunological properties of enolases from muscle, liver and heart have been carried out. 6. It is concluded that the three isoenzymes arise from two independent genetic loci and it is suggested that these evolved from a common ancestral gene 200-300 million years ago.

Aging↗