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Enzyme
Compound
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Query: EC:3.1.3.1 (
alkaline phosphatase
)
47,916
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
A number of methods for the selective enrichment of recombinant plasmids were examined; these include
alkaline phosphatase
treatment of the restricted pBR322 vector, as well as a combination of this and
S1 nuclease
treatment of the ligated mixture of pBR322 and pCR1 plasmids or S. griseus DNA followed by D-cycloserine treatment to enrich for cells carrying recombinant molecules. The relative efficiencies of these methods were compared.
...
PMID:Evaluation of several enrichment procedures for the isolation of recombinant plasmid DNA. 10 33
Modification of the carboxylate groups of purified
S1 nuclease
resulted in a loss of its single-stranded DNAase, RNAase and
phosphomonoesterase
activities. The inactivation was due to the removal of zinc atoms from the enzyme and this in turn was dependent on the degree of modification. While the removal of one zinc atom resulted in the partial inactivation of the enzyme, removal of the remaining zinc atoms resulted in the complete inactivation of the enzyme. Similar results were obtained when the purified enzyme was incubated with various concentrations of the metal chelator, EDTA. The EDTA-(1 mM)-treated enzyme, depleted of one zinc atom, showing 40-45% residual activity, when incubated with 1 mM Zn2+ or 1 mM Co2+, regained a significant amount of its initial activity towards all the substrates. However, Woodward's-Reagent-K-modified enzyme depleted of one zinc atom and having the same level of activity (40-45%) could not regain its activity, indicating that the carboxylate groups are involved in the metal binding. Data obtained with carboxylate-group modification, EDTA-treatment, reconstitution with metal ions, zinc estimation and CD analysis of the enzyme suggests that, out of three zinc atoms present in
S1 nuclease
, zinc I is easily replaceable and is probably involved in the catalytic activity while zinc II and zinc III are involved in maintaining the enzyme structure.
...
PMID:Characterization of S1 nuclease. Involvement of carboxylate groups in metal binding. 128 Oct 97
Some peculiarities of activation of (ADP-ribose) polymerase by DNA fragments were studied. DNA fragments were produced by the digestion of calf thymus DNA by micrococcal nuclease and with a subsequent enzymatic modification of their end groups by
nuclease S1
, polynucleotide kinase of phage T4 and
alkaline phosphatase
. The dependence of the activating effect of DNA on the chemical structure of its end groups was established. It was shown that the terminal phosphate groups are involved in the formation of a catalytically active complex of (ADP-ribose) polymerase with DNA.
...
PMID:[The role of terminal DNA groups in the activation of (ADP-ribose)polymerase]. 139 Dec 6
Modification of the histidine residues of purified
S1 nuclease
resulted in loss of its single-stranded (ss)DNAase, RNAase and
phosphomonoesterase
activities. Kinetics of inactivation indicated the involvement of a single histidine residue in the catalytic activity of the enzyme. Furthermore, histidine modification was accompanied by the concomitant loss of all the activities of the enzyme, indicating the presence of a common catalytic site responsible for the hydrolysis of ssDNA, RNA and 3'-AMP. Substrate protection was not observed against Methylene Blue- and diethyl pyrocarbonate (DEP)-mediated inactivation. The histidine (DEP)-modified enzyme could effectively bind 5'-AMP, a competitive inhibitor of
S1 nuclease
, whereas the lysine (2,4,6-trinitrobenzenesulphonic acid)-modified enzyme showed a significant decrease in its ability to bind 5'-AMP. The inability of the substrates to protect the enzyme against DEP-mediated inactivation, coupled with the ability of the modified enzyme to bind 5'-AMP effectively, suggests the involvement of histidine in catalysis.
...
PMID:Active-site characterization of S1 nuclease. II. Involvement of histidine in catalysis. 146 60
A simple procedure, involving heat-treatment, DEAE-Sephadex, AMP-Sepharose and Bio-Gel P-60 chromatography, was developed for the purification of
S1 nuclease
to homogeneity from commercially available Takadiastase powder. Chemical modification of the amino groups of purified
S1 nuclease
revealed that lysine is essential for single-stranded DNAase, RNAase and
phosphomonoesterase
activities associated with the enzyme. The kinetics of inactivation suggested the involvement of a single lysine residue in the active site of the enzyme. Additionally, lysine modification was accompanied by a concomitant loss of all the activities of the enzyme, indicating the presence of a common catalytic site responsible for the hydrolysis of single-stranded DNA, RNA and 3'-AMP. Substrate-protection and inhibitor-binding studies on enzyme modified with 2,4,6-trinitrobenzenesulphonic acid showed that lysine may be involved in the substrate binding.
...
PMID:Active-site characterization of S1 nuclease. I. Affinity purification and influence of amino-group modification. 163 40
Structural analysis of 55 nearly full-length cDNA clones revealed heterogeneity in the 5'-untranslated regions of rat liver
alkaline phosphatase
mRNAs. The 5' extremities diverged into two totally unrelated sequence stretches at the position 88 nucleotides upstream of the initiation codon ATG. These two sequences, referred to as E1 and E2, were assigned on the genome about 36,000 base pairs (36 kbp) and 10 kbp upstream, respectively, of the exon coding for the 5'-most part of the common region. The gene consisted of 13 exons, including E1 and E2, and spanned about 56 kbp. The 11 exons (E3 to E13) following E1 and E2 were shared in common by the E1-type and the E2-type mRNAs. Analyses by
S1 nuclease
mapping and primer extension revealed the presence of two independent transcription-initiation sites specific to each of the E1 and E2 sequences. These results are interpreted as indicating a possible alternative usage of two leader exons, hence the presence of two independent promoters. Structural features of these putative promoters are described in the context of transcriptional fundamental and regulatory cis-elements.
...
PMID:Isolation and characterization of a rat liver alkaline phosphatase gene. A single gene with two promoters. 254 23
Endogenous oligonucleotides were found in trichloroacetic acid extracts of hamster lung fibroblasts and Tetrahymena cells. Peaks of radioactivity that eluted with retention times similar to oligonucleotide markers (5- to 50-mer) were found by HPLC in cells labeled briefly with 32Pi. Only minute amounts of UV-absorbing material were detected, consistent with a rapid turnover of phosphate groups. The 32P-labeled material also migrated as oligonucleotides on 20% polyacrylamide gels; it was not hydrolyzed by
alkaline phosphatase
but was digested by snake venom phosphodiesterase,
S1 nuclease
, and pancreatic RNase and was phosphorylated by T4 polynucleotide kinase. The 32P-labeled material isolated by HPLC was alkali labile and the hydrolyzate ran as nucleotides on paper chromatography. It is concluded that the oligonucleotides are mainly oligoribonucleotides, but it is possible that oligodeoxynucleotides are also present.
...
PMID:Oligonucleotides with rapid turnover of the phosphate groups occur endogenously in eukaryotic cells. 347 Jul 67
The adenovirus-specific DNA-binding protein (DBP) has been shown to inhibit the hydrolysis of single-stranded DNA by a DNase isolated from KB cells, (Nass, K., and Frenkel, G.D. (1980). J. Virol. 35, 314-319). The specificity of the inhibition has now been investigated. The DBP inhibits the hydrolysis of single-stranded DNA by several different DNases (DNase II, KB DNase,
S1 nuclease
) under a variety of reaction conditions, but it has no effect on DNase I-catalyzed hydrolysis of single-stranded DNA. The DBP also inhibits the rate of hydrolysis of double-stranded DNA by KB DNase and DNase II, but has no effect on DNase I-catalyzed hydrolysis of this substrate. The DBP also inhibits the dephosphorylation of 5'-phosphoryl-terminated DNA by bacterial
alkaline phosphatase
but stimulates the phosphorylation of 5'-hydroxyl-terminated DNA by polynucleotide kinase.
...
PMID:DNase inhibition by the adenovirus DNA-binding protein exhibits specificity for the enzyme but not for the secondary structure of the DNA. 630 53
The DNA fragment containing the phoS gene, a regulatory gene for
alkaline phosphatase
, has been isolated from Escherichia coli K-12 chromosomal DNA by cutting off the DNA with Hind III restriction enzyme and by cloning the gene with plasmid vector pTP 4 which was constructed in this study. The isolated fragment was of about 12.3 kbp and seemed to contain the phoT, glmS, and bgl genes. The 12.3 kbp Hind III fragment was subjected to restriction enzymes EcoR I, BamH I, Sal I, and Pst I, and was found to possess two EcoR I, no BamH I, a Sal I, and four Pst I sites. Partial deletion using these restriction enzymes suggested that the about 6 kbp Hind III-Pst I fragment contained the phoS and phoT genes. Further analysis with other restriction enzymes revealed that the 6 kbp Hind III-Pst I fragment contained a BstE II, two Mlu I and four Hpa I sites. The deletion of these restriction sites using single-strand-specific
nuclease S1
suggested that the BstE II and one of Mlu I sites were in the phoT gene, and the BstE II and two Mlu I sites were not in the phoS gene.
...
PMID:Isolation of DNA fragment containing phoS gene of Escherichia coli K-12. 675 10
A rapid and simplified protocol for in situ hybridization (ISH) with polymerase chain reaction (PCR)-derived single-stranded DNA probes and
S1 nuclease
revealed transcripts of bone matrix proteins on decalcified skeletal bone specimens. Mouse bone tissue was fixed with 4% paraformaldehyde, decalcified with 20% EDTA, and embedded in paraffin. Each pair of primers for reverse transcriptase -PCR was designed to amplify a 280-bp DNA fragment from the coding region of the mature protein of mouse osteonectin (ON) and a 320-bp fragment from the coding region of mouse osteopontin (OP). Initial PCR products were eluted, purified, and reamplified by unidirectional PCR in the presence of the digoxigenin (DIG)-labeled dUTP. ISH was carried out by proteinase K treatment, hybridization, and washing. The unhybridized single-stranded DNA probe was selectively removed by
S1 nuclease
treatment. Hybridized probes were visualized with the
alkaline phosphatase
-conjugated anti-DIG antibody. The transcripts of ON and OP were clearly detected on the thin sections of the decalcified bone. Because this protocol does not require cloning or in vitro transcription, reliable and stable ISH can be done in an ordinary laboratory equipped with a thermal cycler.
...
PMID:In situ hybridization with polymerase chain reaction-derived single-stranded DNA probe and S1 nuclease. 993 Aug 78
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