Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
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Gene/Protein
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Target Concepts:
Gene/Protein
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Enzyme
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Query: EC:2.7.11.1 (
protein kinase
)
81,284
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
A new method of protein nucleation and crystallization based on Langmuir-Blodgett technology is here utilized for the template stimulation of crystal growth of so far non-crystallized proteins. Microcrystals (60-120 microm) of bovine cytochrome P450scc and human
protein kinase
CKII alpha subunit were obtained with use of the homologous protein thin film template by vapor diffusion modified hanging drop method. The induction of microcrystals nucleation by the thin template confirms in the two different important classes of proteins, until now never crystallized, the positive stimulatory influence for crystal formation of protein thin film template, which was observed in an earlier study with a model system (chicken egg white
lysozyme
) as an unexpected acceleration and enhancement in the crystal growth.
...
PMID:Protein nucleation and crystallization by homologous protein thin film template. 1194 80
We have investigated a signal transduction system proposed to allow Streptomyces coelicolor to sense and respond to changes in the integrity of its cell envelope. The system consists of four proteins, encoded in an operon: sigmaE, an RNA polymerase factor; CseA (formerly ORF202), a protein of unknown function; CseB, a response regulator; and CseC, a sensor histidine
protein kinase
with two predicted transmembrane helices (Cse stands for control of sigma E). To develop a sensitive bioassay for inducers of the sigE system, the promoter of the sigE operon (sigEp) was fused to a reporter gene conferring resistance to kanamycin. Antibiotics that acted as inducers of the sigE signal transduction system were all inhibitors of intermediate and late steps in peptidoglycan biosynthesis, including ramoplanin, moenomycin A, bacitracin, several glycopeptides and some beta-lactams. The cell wall hydrolytic enzyme
lysozyme
also acted as an inducer. These data suggest that the CseB-CseC signal transduction system may be activated by the accumulation of an intermediate in peptidoglycan biosynthesis or degradationa. A computer-based searching method was used to identify a sigmaE target operon of 12 genes (the cwg operon), predicted to specify the biosynthesis of a cell wall glycan. In low-Mg(2+) medium, transcription of the cwg operon was induced by vancomycin in a sigE-dependent manner but, in high-Mg(2+) medium, there was substantial cwg transcription in a sigE null mutant, and this sigE-independent activity was also induced by vancomycin. Based on these data, we propose a model for the regulation and function of the sigmaE signal transduction system.
...
PMID:A signal transduction system in Streptomyces coelicolor that activates the expression of a putative cell wall glycan operon in response to vancomycin and other cell wall-specific antibiotics. 1206 6
The predicted polypeptide product of open reading frame sso2387 from the archaeon Sulfolobus solfataricus, SsoPK2, displayed several of the sequence features conserved among the members of the "eukaryotic"
protein kinase
superfamily. sso2387 was cloned, and its polypeptide product was expressed in Escherichia coli. The recombinant protein, rSsoPK2, was recovered in insoluble aggregates that could be dispersed by using high concentrations (5 M) of urea. The solubilized polypeptide displayed the ability to phosphorylate itself as well as several exogenous proteins, including mixed histones, casein, bovine serum albumin, and reduced carboxyamidomethylated and maleylated
lysozyme
, on serine residues. The source of this activity resided in that portion of the protein displaying homology to the catalytic domain of eukaryotic protein kinases. By use of mass spectrometry, the sites of autophosphorylation were found to be located in two areas, one immediately N terminal to the region corresponding to subdomain I of eukaryotic protein kinases, and the second N terminal to the presumed activation loop located between subdomains VII and VIII. Autophosphorylation of rSsoPK2 could be uncoupled from the phosphorylation of exogenous proteins by manipulation of the temperature or mutagenic alteration of the enzyme. Autophosphorylation was detected only at temperatures >or=60 degrees C, whereas phosphorylation of exogenous proteins was detectable at 37 degrees C. Similarly, replacement of one of the potential sites of autophosphorylation, Ser(548), with alanine blocked autophosphorylation but not phosphorylation of an exogenous protein, casein.
...
PMID:Open reading frame sso2387 from the archaeon Sulfolobus solfataricus encodes a polypeptide with protein-serine kinase activity. 1275 43
Listeria monocytogenes is a food-borne pathogen that can cause a variety of illnesses ranging from gastroenteritis to life-threatening septicemia. The beta-lactam antibiotic ampicillin remains the drug of choice for the treatment of listeriosis. We have previously identified a response regulator of a putative two-component signal transduction system that plays a role in the virulence and ethanol tolerance of L. monocytogenes. Here we present evidence that the response regulator, CesR, and a histidine
protein kinase
, CesK, which is encoded by the gene downstream from cesR, are involved in the ability of L. monocytogenes to tolerate ethanol and cell wall-acting antibiotics of the beta-lactam family. Furthermore, CesRK controls the expression of a putative extracellular peptide encoded by the orf2420 gene, located immediately downstream from cesRK. Inactivation of orf2420 revealed that it contributes to ethanol tolerance and pathogenesis in mice. Interestingly, we found that transcription of orf2420 was strongly induced by subinhibitory concentrations of various cell wall-acting antibiotics, ethanol, and
lysozyme
. The induction of orf2420 expression was abolished in the absence of CesRK. Our data suggest that CesRK is involved in regulating aspects of the cell envelope architecture and that changes in cell wall integrity provide a potent stimulus for CesRK-mediated regulation. These results further our understanding of how L. monocytogenes senses and responds to antibiotics that are used therapeutically in the treatment of infectious diseases.
...
PMID:CesRK, a two-component signal transduction system in Listeria monocytogenes, responds to the presence of cell wall-acting antibiotics and affects beta-lactam resistance. 1457 97
Immunomodulation is a commonly used method of prophylaxis in humans and animals. Lysozyme dimer (KLP-602) was used at a dose of 50 ug/kg b.w. in order to correct the immunosuppression caused by the action of herbicide glyphosate (Roundup- Monsanto), which was used in a single bath for 10 minutes in a concentration of 100 mg/l of water. The investigations were carried out on 2 species of fish: the carp (Cyprinus carpio L.) and european catfish (Silurus glanis L.). Herbicide glyphosate caused a decrease in metabolic and phagocytic activity (RBA and
PKA
) and in proliferative response stimulated by Con A and LPS in carp and european catfish. The immunosuppression sustained for about 2 weeks. The results obtained indicate the possibility of correction of immunosuppression applying
lysozyme
dimmer (KLP-602) after use of which, the level of the studied indexes increased.
...
PMID:Modulative influence of lysozyme dimer on defence mechanisms in the carp (Cyprinus carpio) and European sheatfish (Silurus glanis) after suppression induced by herbicide Roundup. 1523 May 44
The regulation of neutrophil functions by Type I
cGMP-dependent protein kinase
(
cGKI
) was investigated in wild-type (WT) and
cGKI
-deficient (
cGKI
-/-) mice. We demonstrate that murine neutrophils expressed cGKIalpha. Similar to the regulation of Ca2+ by
cGKI
in other cells, there was a cGMP-dependent decrease in Ca2+ transients in response to C5a in WT, but not
cGKI
-/- bone marrow neutrophils. In vitro chemotaxis of bone marrow neutrophils to C5a or IL-8 was significantly greater in
cGKI
-/- than in WT. Enhanced chemotaxis was also observed with
cGKI
-/- peritoneal exudate neutrophils (PE-N). In vivo chemotaxis with an arachidonic acid-induced inflammatory ear model revealed an increase in both ear weight and myeloperoxidase (MPO) activity in ear punches of
cGKI
-/- vs WT mice. These changes were attributable to enhanced vascular permeability and increased neutrophil infiltration. The total extractable content of MPO, but not
lysozyme
, was significantly greater in
cGKI
-/- than in WT PE-N. Furthermore, the percentage of MPO released in response to fMLP from
cGKI
-/- (69%) was greater than that from WT PE-N (36%). PMA failed to induce MPO release from PE-N of either genotype. In contrast, fMLP and PMA released equivalent amounts of
lysozyme
from PE-N. However, the percentage released was less in
cGKI
-/- (approximately 60%) than in WT (approximately 90%) PE-N. Superoxide release (maximum velocity) revealed no genotype differences in responses to PMA or fMLP stimulation. In summary, these results show that cGKIalpha down-regulates Ca2+ transients and chemotaxis in murine neutrophils. The regulatory influences of cGKIalpha on the secretagogue responses are complex, depending on the granule subtype.
...
PMID:Neutrophil dysfunction in guanosine 3',5'-cyclic monophosphate-dependent protein kinase I-deficient mice. 1603 36
Inflammatory mediators have been implicated as a cause of reversible myocardial depression in septic shock. We previously reported that the release of
lysozyme
-c (Lmz-S) from leukocytes from the spleen or other organs contributes to myocardial dysfunction in Escherichia coli septic shock in dogs by binding to a cardiac membrane glycoprotein. However, the mechanism by which Lzm-S causes this depression has not been elucidated. In the present study, we tested the hypothesis that the binding of Lzm-S to a membrane glycoprotein causes myocardial depression by the formation of nitric oxide (NO). NO generation then activates soluble guanylyl cyclase and increases cyclic guanosine monophosphate (cGMP), which in turn triggers contractile impairment via activation of
cGMP-dependent protein kinase
(PKG). We examined these possibilities in a right ventricular trabecular preparation in which isometric contraction was used to measure cardiac contractility. We found that Lzm-S's depressant effect could be prevented by the non-specific NO synthase (NOS) inhibitor N(G)-monomethyl-l-arginine (l-NMMA). A guanylyl cyclase inhibitor (ODQ) and a PKG inhibitor (Rp-8-Br-cGMP) also attenuated Lzm-S's depressant effect as did chemical denudation of the endocardial endothelium (EE) with Triton X-100 (0.5%). In EE tissue, we further showed that Lzm-S caused NO release with use of 4,5 diaminofluorescein, a fluorescent dye that binds to NO. The present study shows that the binding of Lzm-S to EE generates NO, and that NO then activates the myocardial guanosine 3',5' monophosphate pathway leading to cardiac depression in sepsis.
...
PMID:Lysozyme binding to endocardial endothelium mediates myocardial depression by the nitric oxide guanosine 3',5' monophosphate pathway in sepsis. 1608 90
Protein kinase A (PKA) activity was detected in the fat body of Galleria mellonella larvae by a non-radioactive method using a specific peptide substrate-kemptide. The enzyme activity was stimulated by cAMP and its analogues: BzcMP, 8-Chl-cAMP and 8-Br-cAMP in concentrations of 1-4muM. Cyclic GMP was not effective in PKA activation. A two-fold increase in PKA activity was detected in the fat body of G. mellonella LPS-challenged larvae. Selective, membrane-permeable PKA inhibitors, H89 and Rp-8-Br-cAMPS, inhibited
protein kinase A
activity in the fat body of G. mellonella larvae in vitro and in vivo. The inhibition of PKA activity in vivo was correlated with a considerable lowering of haemolymph antibacterial activity and a decrease in
lysozyme
content in the fat body of immune challenged larvae. The use of phospho-motif antibodies recognising PKA phosphorylation consensus site allowed identification of four potential PKA phosphorylation substrates of 79, 45, 40 and 36kDa in G. mellonella fat body.
...
PMID:Studies on the role of protein kinase A in humoral immune response of Galleria mellonella larvae. 1673 Jul 43
alpha-Chymotrypsin and
lysozyme
were solubilized in a water/O-[(2-tridecyl, 2-ethyl-1,3-dioxolan-4-yl)methoxy]-O'-methoxy poly(ethylene glycol) (
CK-2
,13 surfactant)/isooctane water-in-oil microemulsion solution at 1.5-2 and 10 g l(-1) for 0.15 and 1.2 M:
CK-2
,13, respectively. Upon contact with an equal volume of 0.1 M: NaH(2)PO(4)/Na(2)HPO(4) buffer, pH 5, a three-phase system (Winsor-III system) was formed, consisting of a surfactant-rich middle phase and aqueous and isooctane-rich "excess" phases. Both enzymes were rapidly released into the aqueous excess phase, with 70% recovery of each in 30 and 60 min for microemulsion solutions containing 0.15 and 1.2 M: surfactant, respectively. The recovered enzymes retained >90% of their original specific activity.
...
PMID:Solubilization of enzymes in water-in-oil microemulsions and their rapid and efficient release through use of a pH-degradable surfactant. 1723 87
The role of
protein kinase A
(
PKA
) in the humoral immune response of the greater wax moth Galleria mellonella larvae to live gram-positive bacteria Micrococcus lysodeikticus and gram-negative bacteria Escherichia coli was investigated. The immune challenge of larvae with both kinds of bacteria caused an increase in fat body
PKA
activity depending on the injected bacteria. Gram-positive M. lysodeikticus was a much better inducer of the enzyme activity than gram-negative E. coli. The
PKA
activity was increased about 2.5-fold and 1.5-fold, after M. lysodeikticus and E. coli injection, respectively. The in vivo inhibition of the enzyme activity by a cell permeable selective
PKA
inhibitor, Rp-8-Br-cAMPS, was correlated with considerable changes of fat body
lysozyme
content and hemolymph antimicrobial activity in bacteria-challenged insects. The kinetics of changes were different and dependent on the bacteria used for the immune challenge of G. mellonella larvae.
...
PMID:The involvement of protein kinase A in the immune response of Galleria mellonella larvae to bacteria. 1731 Nov 9
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