Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:3.1.21.1 (
DNase
)
7,655
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The effect of a low protein (4%) diet on the activity of the hydrolytic enzymes ribonuclease,
deoxyribonuclease
, acid and alkaline phosphatases, beta-glucuronidase and
lysozyme
has been studied in the spleen and thymus of weanling Wistar rats. Experimentation was carried out over 20 and 30 days, and comparisons were made with well-nourished (12% protein) controls. Body weight decreased during the terminal period in protein-deficient animals (P less than 0.001). Spleen and thymus absolute net weights also dropped significantly (P less than 0.001). In terms of organ weight relative to body weight, there was a clear decrease in thymus compared with controls (P less than 0.001). Enzyme activities expressed per total organ fell significantly. Thus, in spleen at 20 days the decrease was maximum in ribonuclease activity (91.15%) and minimum in acid phosphatase activity (44.09%). Thymus decreases ranged from 83.60% activity in beta-glucuronidase and 93.56% in ribonuclease. At 30 days decreases were accentuated; the maximum value in spleen was 92.34%
lysozyme
and, in thymus, 97.09% acid phosphatase. A large increase in hydrolytic activity expressed per milligram of protein was registered, especially at 30 days. This increase reached a maximum of 78.08% beta-glucuronidase in thymus and a minimum of 56.1% alkaline phosphatase; acid phosphatase and ribonuclease activities were not modified. In spleen, however, acid phosphatase (34.00%), alkaline phosphatase (62.50%),
deoxyribonuclease
(39.25%), and beta-glucuronidase (36.01%) increased, but
lysozyme
and ribonuclease enzymes decreased. We concluded that a low protein diet increases catabolism in spleen and thymus through an enhancement of lysosomal hydrolase activities.
...
PMID:Effect of protein deficiency on the lysosomal enzyme activities of the spleen and thymus of weanling rats. 731 May 38
Cell-free extracts were prepared from either freshly grown or spray-dried cells of Micrococcus luteus ATCC 4698 by treatment with
deoxyribonuclease
and
lysozyme
. These extracts converted o-succinylbenzoic acid (OSB) to 1,4-dihydroxy-2-naphthoic acid (DHNA) as shown by spectrophotofluorometric and radioactivity assays. The conversion required the presence of ATP, CoA, and Mg2+. By use of [2-14C]OSB, the simultaneous production of the spirodilactone form of OSB was also demonstrated. The two products formed from OSB was also demonstrated. The two products formed from OSB were further characterized by gas chromatography combined with mass spectrometry. The production of the spirodilactone was suppressed by the addition of a preparation of the enzyme DHNA synthase obtained from Mycobacterium phlei. (This enzyme catalyzes the conversion of a CoA derivative of OSB to DHNA.) On mild acid treatment, the M. luteus extracts retained the ability to produce spirodilactone but lost the ability to form DHNA. These results are interpreted to mean that an OSB-CoA derivative is an intermediate in the conversion of OSB to DHNA by M. luteus and that two enzymes are involved, one to form the OSB-CoA derivative and the second to carry out a cyclization reaction.
...
PMID:Conversion of o-succinylbenzoate to dihydroxynaphthoate by extracts of Micrococcus luteus. 735 57
Increase in the weight of rat parotid glands, decrease in the protein concentration and the activity of alpha-amylase with simultaneous activation of the proteolytic enzymes (caseinolytic activity at pH 7.6, activity of cathepsins at pH 5.5) were observed in pyo-traumatic parotiditis. Local administration of the protease inhibitor (contrical) or intramuscular treatment with trypsin showed the positive medical effect--decrease of the gland weight, increase in the protein concentration and in the alpha-amylase activity together with lowering in the activity of proteinases. Intramuscular administration of antimicrobic enzymes (
lysozyme
, RNase,
DNAase
) did not affect the pyo-traumatic parotiditis. Application of proteolytic enzymes or their inhibitors is recommended for clinical treatment of parotidites.
...
PMID:[Effect of a number of enzyme preparations on the course of experimental parotitis]. 745 17
L-[4,5-3H]- or L-[U-14C]leucine was incorporated by Bacteroides thetaiotaomicron into acid-precipitable material even when the bacteria were treated with concentrations of tetracycline high enough to prevent growth. Similar results were obtained when L-[2,3,4-3H]valine or L-[4,5-3H]isoleucine was used instead of leucine. In bacteria which had been treated with tetracycline, the acid-precipitable label was not solubilized by treatment with protease,
lysozyme
, or
deoxyribonuclease
. However, virtually all of the label was extractable with chloroform-methanol, indicating that the label had been incorporated into membrane lipids. Since L-[1-14C]leucine was not incorporated into lipids, leucine was probably decarboxylated before incorporation. When a chloroform extract from bacteria which had been labeled with both [32P]phosphate and [3H]leucine was resolved into component phospholipids by two-dimensional thin-layer chromatography, 3H was incorporated into all of the phospholipids. When these phospholipids were deacylated, the 3H from leucine was associated with released fatty acids rather than with the head groups. Thus, it appears that B. thetaiotaomicron can utilize leucine and similar amino acids not only by incorporating them into protein but also by incorporating portions of these amino acids into membrane phospholipids.
...
PMID:Incorporation of leucine into phospholipids of Bacteroides thetaiotaomicron. 746 55
Treatment of Pseudomonas aeruginosa with metal ion chelators, especially ethylenediaminetetraacetic acid (EDTA), causes both release of protein-lipopolysaccharide complexes and cell death. We have examined the effect of EDTA on P. aeruginosa and found that EDTA does not induce the rapid solubilization of the peptidoglycan sacculus and complete lysis as previously thought; the decrease in optical density of cultures incubated with EDTA is primarily due to the loss of the outer membrane. Of the other potential solubilizers examined, only ethylene-bis(oxyethylenenitrilo)tetraacetic acid (EGTA) resulted in some decrease in optical density. The lytic effect of EDTA on 12 strains of P. aeruginosa was examined and was found to vary greatly between strains; the sensitivity to EDTA varies from between 96% and 10% of the decrease in optical density resulting from incubation of cells with both EDTA and
lysozyme
. Sensitivity to EDTA is not constant during the growth of P. aeruginosa; in the early exponential phase of growth, cells treated with EDTA exhibit a 82% decrease in optical density after 30 min while in the stationary phase the optical density decreases by only 40%. Nucleic acids were observed to leak from cells following treatment with EDTA and this was greatly facilitated by
DNase
and RNase. The release of genetic material was much reduced when cells were incubated at 4 degrees C, supporting an enzymatic role in cell wall solubilization. We propose that only small areas of the sacculus become hydrolysed via specific peptidoglycan hydrolases, or autolysin(s), which are activated or de-regulated by EDTA.
...
PMID:Role of autolysins in the EDTA-induced lysis of Pseudomonas aeruginosa. 800 62
The percentage of bacteriocin-producing and phage-producing Klebsiella strains was as follows: K. pneumoniae-10%, K. ozaenae-7%, K. rhinoscleromatis-9%. The antimicrobial spectrum of the studied inducible particler was broad and was not limited by the frames of the genus and family. Bacteriocins and bacteriophages from Klebsiella were active to Klebsiella, Enterobacter, Escherichia, Shigella and Proteus representatives significant in medicine. Klebocins and Klebsiella phages exhibited antagonistic effects to phytopathogenic bacteria. Some strains of Erwinia and Pseudomonas were sensitive to phages or bacteriocins from Klebsiella. Bacteriocins protected corn and tomato seeds from contamination by erwinioses agents. All cultures of Agrobacterium, Corynebacterium, Micrococcus, Staphylococcus, Streptococcus were resistant to action of phages and klebocins. Bacteriocins from Klebsiella were assayed for their sensitivity to trypsin, chymotrypsin,
lysozyme
, ribonuclease,
deoxyribonuclease
. Action of klebocins was associated with a protein component. Proceeding from data of diffusion through the disc ultrafiltration membranes molecular weight of klebocins was in the range of 30,000 and 50,000 Da.
...
PMID:[The antimicrobial spectrum of the action of bacteriocins and bacteriophages from Klebsiella strains]. 816 98
Identification of Na+ binding sites in protein crystals is complicated by comparable electron density of this monovalent cation and water. Valence calculations can predict the location of metal ion binding sites in proteins with high precision. These calculations were used to screen 332,242 water molecules in 2742 protein structures reported in the Protein Data Bank (PDB), searching for molecules with Na+/- specific valence values V(Na+) > or = 1.0 v.u., as expected for a bound Na ion. Thirty-three water molecules (<0.01% of the total) were found be have V(Na+) > or = 1.0 v.u. and to be located within 3.5 A from at least two protein oxygen atoms. These water molecules, with a high Na+ -specific valence, do not have valences specific for other cations, like Li+, K+, Mg2+ or Ca2+. They belong to nine different proteins (
deoxyribonuclease I
, enolase, hen egg-white
lysozyme
, human
lysozyme
, phospholipase A2, proteinase A, rubredoxin, thrombin and phage T4
lysozyme
) and appear with similar coordination geometry, typically octahedral, in the same place in multiple crystal structure determinations of the same protein. In the case of thrombin, the water molecule singled out by valence calculations is, in fact, a bound Na ion as demonstrated by molecular replacement with Rb+. Valence calculations provide an accurate screening of water in protein crystals and may help identify Na+ binding sites of functional importance.
...
PMID:Valence screening of water in protein crystals reveals potential Na+ binding sites. 859 92
We have discovered that T7 RNA polymerase, purified to apparent homogeneity from overexpressing Escherichia coli cells, possesses a
DNase
and an RNase activity. Mutations in the active center of T7 RNA polymerase abolished or greatly decreased the nuclease activity. This nuclease activity is specific for single-stranded DNA and RNA oligonucleotides and does not manifest on double-stranded DNAs. Under the conditions of promoter-driven transcription on double-stranded DNA, no nuclease activity was observed. The nuclease attacks DNA oligonucleotides in mono- or dinucleotide steps. The nuclease is a 3' to 5' exonuclease leaving a 3'-OH end, and it degrades DNA oligonucleotides to a minimum size of 3 to 5 nucleotides. It is completely dependent on Mg2+. The T7 RNA polymerase-nuclease is inhibited by T7
lysozyme
and heparin, although not completely. In the presence of rNTPs, the nuclease activity is suppressed but an unusual 3'-end-initiated polymerase activity is unmasked. RNA from isolated pre-elongation and elongation complexes arrested by a psoralen roadblock or naturally paused at the 3'-end of an oligonucleotide template exhibited evidence of nuclease activity. The nuclease activity of T7 RNA polymerase is unrelated to pyrophosphorolysis. We propose that the nuclease of T7 RNA polymerase acts only in arrested or paused elongation complexes, and that in combination with the unusual 3'-end polymerizing activity, causes heterogeneity in elongation complexes. Additionally, during normal transcription elongation, the kinetic balance between nuclease and polymerase is shifted in favor of polymerase.
...
PMID:Nuclease activity of T7 RNA polymerase and the heterogeneity of transcription elongation complexes. 907 96
Intact cells of aminoglycoside (AG) antibiotic-resistant Pseudomonas aeruginosa usually do not inactivate AG, even though they possess the AG-modifying enzyme. An assay method for determining the activity of inactivating enzyme in intact cells of streptomycin-resistant P. aeruginosa was previously reported. Although this assay method was applied to the determination of the activity of kanamycin (KM)-inactivating enzymes, it could not apply to some of the KM-resistant strains. A new simple assay method has now been investigated for determining the activity of KM-inactivating enzyme in intact cells of clinically isolated KM-resistant P. aeruginosa. The determination of AG-inactivating enzyme activity was attempted using
lysozyme
for release of the inactivating enzymes in washed cells, and both
DNase
and RNase were added to digestion of the nucleic acids released by bacteriolysis. This
lysozyme
-
DNase
-RNase (LDR) method has facilitated the confirmation of the presence of AG-inactivating enzyme in the strains used. In addition, the LDR technique was applicable to the determination of inactivating enzyme activity for various AGs other than KM. Since this simple assay method can determine any type of AG-inactivating enzyme activity of various P. aeruginosa strains, it may contribute significantly to the rapid selection of drugs in clinical use.
...
PMID:A new simple assay for determining aminoglycoside inactivation in intact cells of Pseudomonas aeruginosa. 941 36
A method was developed for extraction of DNA from Chroococcidiopsis that overcomes obstacles posed by bacterial contamination and the presence of a thick envelope surrounding the cyanobacterial cells. The method is based on the resistance of Chroococcidiopsis to
lysozyme
and consists of a
lysozyme
treatment followed by osmotic shock that reduces the bacterial contamination by 3 orders of magnitude. Then
DNase
treatment is performed to eliminate DNA from the bacterial lysate. Lysis of Chroococcidiopsis cells is achieved by grinding with glass beads in the presence of hot phenol. Extracted DNA is further purified by cesium-chloride density gradient ultracentrifugation. This method permitted the first molecular approach to the study of Chroococcidiopsis, and a 570-bp fragment of the gene ftsZ was cloned and sequenced.
...
PMID:A method for DNA extraction from the desert cyanobacterium chroococcidiopsis and its application to identification of ftsZ 975 40
<< Previous
1
2
3
4
5
6
7
8
9
Next >>