Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:4.1.99.3 (PRE)
 1,923 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The activity of purified DNA photolyase from Baker's yeast is enhanced by a compound (Activator (III)) obtained from yeast by chloroform extraction ion exchange chromatography and gel filtration. Thin layer chromatography and spectral data indicate that the compound is homogeneous. Activator III emits at 350 and 440 nm when excited at 290 nm, and emits at 440 nm when excited at 358 nm. After acid hydrolysis, emission at 440 nm is produced only by excitation at 358 nm, indicating that activator (III) contains two separate chromophoric moieties. The chromophore excited by 358 nm light has a pK of 9-11, while the other chromophore has a pK of 4-5, and possibly of 9-11. The enhancement of photolytic activity by activator (III) at a concentration equimolar with that of the enzyme and the similarity of the fluorescent spectra of the activator with that of heat-denatured photolyase, suggests that the activator may be the chromophore associated with the enzyme.
Biochim Biophys Acta 1976 Dec 01
PMID:Purification from baker's yeast of an activator of DNA photolyase. 1 32

1. Bacteroids of Rhizobium leguminosarum (strain PRE) purified from root nodules of Pisum sativum (var. 'Rondo') by the standard procedure of differential centrifugation contained considerable contamination of mitochondrial material. This could be removed by incubation of the bacteroid preparation with 1 M KCl/1% deoxycholate. 2. The DNA content of bacteroid cells of R. leguminosarum was found to have increased about three fold in comparison with the DNA content of free living R. leguminosarum bacteria. 3. No significant difference in DNA composition of free living R. leguminosarum bacteria and bacteroids could be detected by CsCl equilibrium centrifugation, RNA - DNA hybridization and DNA - DNA reassociation studies.
Biochim Biophys Acta 1975 Dec 04
PMID:A comparison of DNA from free living and endosymbiotic Rhizobium leguminosarum (strain PRE). 17 57

A new technique is developed for physically enriching recombinant DNA molecules in an in vitro recombination mixture. UV-irradiation of the donor DNA before recombination enables photoreactivating enzyme (PRE) (deoxyribodipyrimidine photolyase, EC 4.1.99.3) to attach to the donor segments in recombinant molecules. This attached protein causes retention of the recombinant molecules on a nitrocellulose filter, while molecules not containing donor DNA pass through. The bound DNA is repaired of its UV damage and released for insertion into cells by exposure to photoreactivating light in situ, yielding approx. 350-fold enrichment. Although applicable to any gene, this procedure has been used in cloning the Escherichia coli phr gene itself, permitting 100-fold amplification of the gene product in vivo.
Gene 1978 Dec
PMID:Cloning of the phr gene and amplification of photolyase in Escherichia coli. 36 54

Relations and quocientes of cerebrospinal fluid (CSF) immunoglobulins G (IGG) and serum (S) IGG were studied in 50 patients with chronic headache, normal neurological examination and normal electroencephalogram. CSF was normal as to: pressure, cytology, total proteins, protein fractions and immunoglobulins (IGG, IGA and IGM) contents. In all cases the CSF sample studied was collected from cisterna magna. The relations and quocients studied were: CSF IGG/CSF TOTAL PROTEIN, CSF IGG/CSF ALBUMIN, CSF IGG/CSF PRE ALBUMIN+ALBUMIN, (CSF IGG/S IGG) / (CSF ALBUMIN/S ALBUMIN) and (CSF IGG/S IGG) / (CSF PRE ALBUMIN+ALBUMIN) / (S ALBUMIN). It was found that the best index to appraise the behavior of IGG is: (CSF IGG/S IGG) /(CSF PRE ALBUMIN+ALBUMIN/S ALBUMIN) that shows an average of 0.56 and a standard deviation of 0.32 in the material studied.
Arq Neuropsiquiatr 1979 Dec
PMID:[Immunoglobulins of the normal cerebrospinal fluid. II. Relations and indices]. 53 87

The PRE repairs DNA by the specific and exclusive monomerization of pyrimidine dimers. Photoreactivation thus provides an analytical test for determining the role of pyrimidine dimers in UV damage to biologic systems. We have shown the first UV transformation of cultured human cells (judged by ability to grow in soft agar). Preliminary results indicate that 1) lesions leading to cell transformation are subject to photoreactivation and 2) pyrimidine dimers may well be important in solar carcinogenesis.
Natl Cancer Inst Monogr 1978 Dec
PMID:Photoreactivation: evaluation of pyrimidine dimers in ultraviolet radiation-induced cell transformation. 75 70

Two haploid radiation-sensitive mutants of Saccharomyces were studied to investigate the formation of complex between photoreactivating-enzyme and substrate after ultra-violet irradiation. Using photo-flashes, the time necessary for maximum complex formation has been determined. Within 1 min, 70 per cent of the complexes have been formed. To determine the number of photoreactivating enzyme molecules per cell, the maximum dose decrement obtained after one photo-flash was determined and corrected for the effects of non-photoreactivable lesions. The corrected maximum dose decrement was found to be identical for both strains (8-5 erg mm-2). The number of photoreactivating-enzyme molecules involved in the photorepair of nuclear DNA damage was calculated as 272 +/- 27.
Int J Radiat Biol Relat Stud Phys Chem Med 1975 Dec
PMID:Determination of the number of photoreactivating enzyme molecules per haploid Saccharomyces cells. 108 62

Yeast DNA photolyase, purified by affinity chromatography, ran as a single component when analyzed by either electrophoresis on polyacrylamide gradient gels or by sedimentation velocity through 5-20% sucrose gradients containing 0.4 M KCl, and, therefore, was considered homogeneous. The molecular weights of photolyase, determined by these methods, were 130000 and 136000, respectively. When the enzyme was examined by electrophoresis on sodium dodecyl sulfate polyacrylamide gradient gels, it dissociated into two bands whole molecular weights were 60000 and 85000. After the enzyme was sedimented through sucrose gradients in the presence of 1.0 M KCl, two absorbance maxima, which corresponded to polypeptides of 54000 and 82500, were found in the fractions collected. Thus, the enzyme consists of two dissimilar subunits. When the two fractions that exhibited maximal absorbance were mixed together, a time-dependent increase in activity occurred, demonstrating that active enzyme could be reconstituted from these subunits. Analysis of sucrose gradients containing 1.0 M salt for photolyase activity showed that it was present exclusively in the region of the gradient corresponding to 68200 in agreement with a previous report (J. Cook and T. Worthy (1972), Biochemistry 11, 388). These active fractions were found in the overlap region between the two subunits, and their activity was attributed to reconstitution of the enzyme during the assay.
Biochemistry 1975 Dec 16
PMID:Yeast DNA photolyase: molecular weight, subunit structure, and reconstruction of active enzyme from its subunits. 110 68

By introducing and expressing a cDNA library constructed from mRNA of the cultured goldfish Carassius auratus cells in Escherichia coli, a gene encoding photolyase of the vertebrate was isolated, the first example from metazoa. The amino acid sequence deduced from the nucleotide sequence differs significantly from those of microorganisms. Five out of 6 tryptophan residues strictly conserved in photolyases from microorganisms and thought to play important roles in DNA and chromophore binding of the enzyme are substituted by other residues of different characteristics. By Northern analysis the expression of the photolyase gene was found to be induced more than 10 times by exposure of the cells to visible light. These results indicate a unique evolution of the photolyase gene and a novel mechanism of gene regulation, in which visible light triggers the production of the light-dependent enzyme for repair of DNA damages induced by harmful ultraviolet part of sunlight.
J Biol Chem 1992 Dec 25
PMID:Visible light-inducible photolyase gene from the goldfish Carassius auratus. 133 47

Plasma norepinephrine (NE) increases from rest to exercise during normoxic exercise, and significantly more during hypoxic exercise in goats. To determine carotid body (CB) mediated effects of increased NE on ventilatory control, we investigated ventilatory responses to intracarotid NE infusions in awake, resting goats. NE was infused (0.5-5.0 micrograms.kg-1 x min-1, 2-3 min) into either a CB intact or contralateral CB-denervated carotid artery in both normoxia and hypoxia (FIO2. = 0.11). PRE-infusion measurements of arterial blood gases, blood pressure and pulmonary ventilation (VI) were compared with values 30-45 sec after beginning NE infusions at 1.0 micrograms.kg-1 x min-1. On the CB-intact side, NE infusions decreased VI by an average of 43% (P < 0.05) and increased PaCO2 4.0 +/- 0.3 mmHg (P < 0.05); ventilatory inhibition preceded an increase in arterial blood pressure. NE infusions on the CB-denervated side had no significant effects on VI or PaCO2, but still increased blood pressure to the same level as infusions on the CB-intact side. In hypoxia, NE infusions on the intact side no longer inhibited VI. NE induced VI inhibition in normoxia was similar in magnitude and time course to dopamine induced VI inhibition. Experiments were repeated following administration the alpha-adrenergic receptor antagonist, phenoxybenzamine (1 mg.kg-1, i.v.) the beta-adrenergic receptor antagonist, propranolol (1 mg.kg-1, i.v.) and the D2-dopamine receptor antagonist, domperidone (1 mg.kg-1, i.v.). Phenoxybenzamine partially blocked NE induced ventilatory depression and domperidone blocked it, but propranolol had no effect. These data indicate that NE inhibits ventilation in goats via effects on carotid chemoreceptors. NE induced inhibition is independent of changes in blood pressure or baroreceptor feedback, and appears to involve both alpha-adrenergic and D2-dopaminergic receptors.
Respir Physiol 1992 Dec
PMID:Intracarotid norepinephrine infusions inhibit ventilation in goats. 148 Aug 41

The PHR1 gene of Saccharomyces cerevisiae encodes the DNA repair enzyme photolyase. Transcription of PHR1 increases in response to treatment of cells with 254-nm radiation and chemical agents that damage DNA. We report here the identification of a damage-responsive DNA binding protein, termed photolyase regulatory protein (PRP), and its cognate binding site, termed the PHR1 upstream repression sequence, that together regulate induction of PHR1 transcription after DNA damage. PRP activity, monitored by electrophoretic-mobility-shift assay, was detected in cells during normal growth but disappeared within 30 min after irradiation. Copper-phenanthroline footprinting of PRP-DNA complexes revealed that PRP protects a 39-base-pair region of PHR1 5' flanking sequence beginning 40 base pairs upstream from the coding sequence. A prominent feature of the foot-printed region is a 22-base-pair palindrome. Deletion of the PHR1 upstream repression sequence increased the basal level expression of PHR1 in vivo and decreased induction after exposure of cells to UV radiation or methyl methanesulfonate, whereas insertion of the PRP binding site between the CYC1 upstream activation sequence and "TATA" sequence reduced basal level expression and conferred damage responsiveness upon a reporter gene. Thus these observations establish that PRP is a damage-responsive repressor of PHR1 transcription.
Proc Natl Acad Sci U S A 1991 Dec 15
PMID:A damage-responsive DNA binding protein regulates transcription of the yeast DNA repair gene PHR1. 176 39


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