Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.2.1.17 (lysozyme)
 21,489 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We screened various Bacillus species producing transglutaminase (TGase), measured as labeled putrescine incorporated into N,N-dimethylcasein. As a result, we detected TGase activity in sporulating cells of B. subtilis, B. cereus, B. alvei and B. aneurinolyticus, and found TGase activity related to sporulation. TGase activity of Bacillus subtilis was detected in lysozyme-treated sporulating cells during late sporulation, but not in cells without lysozyme treatment or the supernatant of the culture broth. TGase was found to be localized on spores. TGase was preliminarily purified by gel filtration chromatography for characterization. Its activity was eluted in the fractions indicating a molecular weight of approximately 23 kDa. TGase could cross-link and polymerize a certain protein. The enzyme was strongly suggested to form epsilon-(gamma-glutamyl)lysine bonds, which were detected in the spore coat proteins of B. subtilis. The activity was Ca(2+)-independent like the TGases derived from Streptoverticillium or some plants. It is suggested that TGase is expressed during sporulation and plays a role in the assembly of the spore coat proteins of the genus Bacillus.
J Gen Appl Microbiol 1998 Feb
PMID:Transglutaminase in sporulating cells of Bacillus subtilis. 1250 Dec 97

The cells of Haloarcula vallismortis, an extreme halophilic archaebacterium, were permeabilized by various chemical, physical, and biological treatments. Biological permeabilization by lysozyme and papain showed effective results as observed by studying the in situ activity of halophilic glyceraldehyde-3-phosphate dehydrogenase (hGAPDH) as the model enzyme. Detergents N-cetyl-N, N, N-trimethyl ammonium bromide (CTAB) and digitonin also showed significant results. Other strains of halobacteria could also be permeabilized by lysozyme. The cell morphology did not show any significant change after permeabilization as observed by phase contrast microscopy. The enzyme characteristics of hGAPDH were studied in situ using permeabilized H. vallismortis cells. The properties, like optimum pH, Km for GAP and NAD(+), inhibition by heavy metals, sulphydryl reagents, and other compounds, showed remarkable similarity with those studied in vitro.
J Gen Appl Microbiol 1997 Jun
PMID:Measurement of in situ halophilic glyceraldehyde-3-phosphate dehydrogenase activity from the permeabilized cells of archaebacterium Haloarcula vallismortis. 1250 32

Earlier, three genes Ds1, Ds2, and Ds3 encoding corresponding destabilase-lysozyme isoforms were identified. However only one form of the enzyme encoded by Ds3 gene coincided with the protein CNBr fragments [Mol. Gen. Genet. 253 (1996) 20]. In this work we found by ESI-TOF mass spectrometry that the enzyme preparation consists of at least three forms with molecular masses of 12677.6, 12839.7, and 12938.2Da, each of which contains seven disulfide bridges. Only one mass (12839.7Da) fits to the calculated mass for the protein encoded by Ds3 gene. Further analysis of the CNBr fragments of the enzyme showed the heterogeneity of large 5.5 kDa peptide at positions 64 (threonine or arginine) and 67 (histidine or arginine) in the wild-type amino acid sequence. One CNBr peptide, with Arg and His at positions 64 and 67, respectively, correlates in the molecular mass with the protein encoded by Ds3. In addition, we have found a new acid form of destabilase-lysozyme, P-Ac, which differs from all known destabilase-lysozyme structures by its N-terminal amino acid sequence.
 ...
PMID:Multiple forms of medicinal leech destabilase-lysozyme. 1278 7

Cell multiplication and phage formation of lysogenic B. megatherium cultures have been determined under various conditions and in various culture media. 1. In general, the more rapid the growth of the culture, the more phage is produced. No conditions or culture media could be found which resulted in phage production without cell growth. 2. Cultures which produce phage grow normally, provided they are shaken. If they are allowed to stand, those which are producing phage undergo lysis. Less phage is produced by these cultures than by the ones which continue to grow. 3. Cells plated from such phage-producing cultures in liquid yeast extract medium grow normally on veal infusion broth agar or tryptose phosphate broth agar, which does not support phage formation, but will not grow on yeast extract agar. 4. Any amino acid except glycine, tyrosine, valine, leucine, and lysine can serve as a nitrogen source. Aspartic acid gives the most rapid cell growth. 5. The ribose nucleic acid content is higher in those cells which produce phage. 6. The organism requires higher concentrations of Mg, Ca, Sr, or Mn to produce phage than for growth. 7. The lysogenic culture can be grown indefinitely in media containing high phosphate concentrations. No phage is produced under these conditions, but the cells produce phage again in a short time after the addition of Mg. The potential ability to produce phage, therefore, is transmitted through cell division. 8. Colonies developed from spores which have been heated to 100 degrees C. for 5 minutes produce phage and hence, infected cells must divide. 9. No phage can be detected after lysis of the cells by lysozyme.
J Gen Physiol 1951 May
PMID:Growth and phage production of lysogenic B. megatherium. 1483 49

Periods of stress are often associated with disease outbreaks in cultured fish, and stress is often characterized by the secretion of cortisol. Although stress and cortisol secretion are highly correlated in fish, the role of cortisol in affecting channel catfish (Ictalurus punctatus) pathogen susceptibility is unclear. The effects of short-term stress and exogenous cortisol administration on channel catfish susceptibility to Edwardsiella ictaluri, the etiologic agent of enteric septicemia of catfish (ESC), were investigated. Channel catfish were exposed to virulent E. ictaluri following a standardized 30-min low-water stress or administration of dietary cortisol (100 mg/kg feed) and compared to a pathogen-challenged control group of catfish. Pathogen susceptibility increased in stressed catfish (43.3% mortality) when compared to cortisol-fed catfish (26.7%) and controls (26.7%). A greater (P<0.05) percentage of stressed catfish (25.9%) tested positive for E. ictaluri relative to cortisol-fed catfish (13.0%) over the course of the study, however, average levels of circulating bacteria were not different (P>0.05) among the treatments. Catfish challenged by the low-water stress event had elevated (P<0.05) circulating levels of cortisol 1-day post-pathogen exposure and elevated (P<0.05) lysozyme activity 4 and 14 days post-pathogen exposure when compared to cortisol-fed and control-challenged catfish. Cortisol concentrations were not correlated (P>0.05) to either lysozyme activity or bacterial levels; however, lysozyme activity was positively correlated (P=0.0197) to blood bacterial concentrations. These results implicate other stress factors or pathways, separate from or possibly in conjunction with cortisol, in the stress-associated immunosuppression of channel catfish as it relates to ESC susceptibility.
Gen Comp Endocrinol 2005 May 15
PMID:Effects of cortisol and stress on channel catfish (Ictalurus punctatus) pathogen susceptibility and lysozyme activity following exposure to Edwardsiella ictaluri. 1586 71

Transactivation experiments were performed involving the genetically related Salmonella phages P22, L and Px1 in order to find out if more than one positively acting regulatory product is engaged in the expression of vegetative gene functions of each of these phages. The results obtained with Px1- and L-lysogenic cells superinfected with P22 suggest the following conclusions: 1. The expression of the early genes 12 and 23 and of the late gene 19 (lysozyme synthesis) is positively regulated by two different regulatory products, since P22 transactivates in prophage Px1 both early and late genes (Prell, 1973), in prophage L only late genes. 2. The transactivation by P22 of the lysozyme gene of prophage L takes place in the presence of L repressor. This conclusion is suggested, since the superinfecting P22 does not derepress early gene expression (see 1.), and is confirmed by demonstration of replication inhibition for L phage in L lysogenic cells doubly superinfected with L and P22 phages (Thomas-Bertani-experiment). 3. The late gene regulatory protein seems to be synthesized by gene 23, as transactivation experiments with both L- and Px1 prophages suggest. 4. The expression of gene 23 itself is turned on by an early regulatory product. The gene which codes for it is still unidentified. However its product seems to by highly specific, since it is active on Px1- but not on L-prophage.
Mol Gen Genet 1975
PMID:Regulation of gene expression in Salmonella phage P22. II. Regulation of expression of late functions. 1609 2

Growth hormone (GH) transgenic amago salmon (Oncorhynchus masou) were generated with a construct containing the sockeye salmon GH1 gene fused to the metallothionein-B (MT-B) promoter from the same species. This transgene directed significant growth enhancement with transgenic fish reaching approximately four to five times greater weight than control salmon in F(2) and F(3) generations. This drastic growth enhancement by GH transgene is well known in fish species compared with mammals, however, such fish can show morphological abnormalities and physiological disorders like other GH transgenic animals. GH is known to have many acute effects, but currently there are no data describing the chronic effects of over-expression of GH on various hepatic genes in GH transgenic fish. Hepatic gene expression is anticipated to play very important roles in many physiological functions and growth performance of transgenic and control salmon. To examine these effects, we performed subtractive hybridization (using cDNA generated from liver RNA) in both directions to identify genes both increased and decreased in transgenic salmon relative to controls (576 clones were isolated and sequenced in total). Heme oxygenase, vitelline envelope protein, Acyl-coA binding protein, NADH dehydrogenase, mannose binding lectin-associated serine protease, hemopexin-like protein, leucyte-derived chemotaxin2 (LECT2), and many other genes were obtained in higher clone frequencies suggesting enhanced expression. In contrast, complement C3-1, lectin, rabin, alcohol dehydrogenase, Tc1-like transposase, Delta6-desaturase, and pentraxin genes were obtained in lower frequencies. Microarray analysis was also performed to obtain quantitative expression data for these subtracted cDNA clones. Analysis of fish across seasons was also conducted using both F(2) and F(3) salmon. Results of the microarray data essentially corresponded with those of the subtraction data when both F(2) and F(3) fish were completely immature, but the expression pattern was changed when fish approached maturation. Genes showing enhanced expression in GH transgenic fish in F(2) and F(3) by array analysis were vitelline envelope protein, hemopexin-like protein, heme-oxygenase, inter alpha-trypsin inhibitor, LECT2, GTP cyclohydrolase I feedback regulatory protein (GFRP), and bikunin. Reduced expression genes were lectin, Delta6-desaturase, apolipoprotein, and pentraxin. In particular, lectin was found to be highly suppressed in all F(2) and immature F(3) salmon. Further, serum lysozyme activity, one of innate immunity, was significantly (p<0.05) decreased in both F(2) and F(3) GH transgenic fish. These results indicate that the GH transgene fish had altered hepatic gene expression relating to iron-metabolism, innate immunity, reproduction, and growth.
Gen Comp Endocrinol 2007 Mar
PMID:Changes in hepatic gene expression related to innate immunity, growth and iron metabolism in GH-transgenic amago salmon (Oncorhynchus masou) by cDNA subtraction and microarray analysis, and serum lysozyme activity. 1722 41

This paper reviews the immunomodulatory effects, extra-pituitary expression and paracrine action of growth hormone (GH), and a possible role of GH/insulin-like growth factor-I (IGF-I) axis in the immune system of teleost fish. In some euryhaline fish, the activation of immune functions observed during seawater acclimation appears to be associated with the osmoregulatory action of GH. Administration of GH enhances many aspects of immune functions including non-specific defences; cytotoxic, phagocytic, haemolytic and lysozyme activities. GH also activates immunoglobulin production as a specific defense and increases ceruloplasmin levels as an acute-phase protein. The GH gene is also expressed in many extra-pituitary tissues of fish, especially in lymphoid organs and cells. Several endocrine factors appear to act on immune function through modification of GH secretion from fish leucocytes. Exposure of phagocytic leucocytes of tilapia to IGF-I in vitro stimulated proliferation and superoxide production associated with phagocytosis. Exposure to GH had no significant effect on IGF-I secretion from tilapia leucocytes, despite of the fact that they secreted significant amounts of IGF-I. GH and IGF-I appear to act in a paracrine manner in the regulation of the teleostean immune system. Further studies are necessary to characterize the interactions of GH with other endocrine and paracrine factors.
Gen Comp Endocrinol
PMID:Growth hormone and fish immune system. 1738 28

We investigated the effect of ploidy on osmoregulatory, stress and immune responses in non-smolting rainbow trout during saltwater adaptation. Sibling groups of diploid and triploid trout were acclimated in freshwater (FW) and then subjected to abrupt transfer to full strength (35ppt) saltwater (SW) or back to FW. Fish were sampled pre-stress, and 1, 3, 6, 12, 24, 48, 72 and 168h post-stress. Overall mortality in SW was less than 5% in either ploidy, with no mortality in FW. Significant elevations in plasma osmolality and gill ATPase were observed within 1-3h of SW transfer, but retuned to basal levels within 72h indicative of rapid saltwater adaptation and did not differ between ploidy. Furthermore, FW-SW transfer also caused significant and sustained elevations in total blood haemoglobin, plasma IGF-I, cortisol, glucose, total white blood cell counts, increased plasma but decreased mucus lysozyme, and enhanced head kidney macrophage respiratory burst activity. Conversely, FW-FW transfer evoked more transient and less elevated responses, more typical of primary and secondary responses to a single stressor. We conclude that the more elevated levels in these parameters are a function of saltwater adaptation as well as the generic stress response, and that this did not differ between ploidy. Strong positive correlations were found between plasma IGF-I and cortisol, and with osmolality, glucose and WBC, while a negative correlation was found with plasma lysozyme irrespective of ploidy. Overall, the current results suggest that triploidy does not affect the ability of non-smolting trout to adapt to full strength seawater under optimum conditions, and that the osmotic and stress response to such transfer is similar to diploids.
Gen Comp Endocrinol
PMID:The influence of ploidy on saltwater adaptation, acute stress response and immune function following seawater transfer in non-smolting rainbow trout. 1743 69

Influence of environmental salinity on expression of distinct corticosteroid receptor (CR) genes, glucocorticoid receptor (GR)-1 and -2, and mineralcorticoid receptor (MR), was examined in osmoregulatory and hemopoietic organs and leucocytes of steelhead trout (Oncorhynchus mykiss). There was no significant difference in plasma cortisol levels between freshwater (FW)- or seawater (SW)-acclimated trout, whereas Na+, K+-ATPase was activated in gill of SW fish. Plasma lysozyme levels also showed a significant increase after acclimation to SW. In SW-acclimated fish, mRNA levels of GR-1, GR-2, and MR were significantly higher in gill and body kidney than those in FW. Head kidney and spleen showed no significant change in these CR mRNA levels after SW-acclimation. On the other hand, leucocytes isolated from head kidney and peripheral blood showed significant decreases in mRNA levels of CR in SW-acclimated fish. These results showed differential regulation of gene expression of CR between osmoregulatory and immune systems.
Gen Comp Endocrinol 2008 May 01
PMID:Effects of seawater acclimation on mRNA levels of corticosteroid receptor genes in osmoregulatory and immune systems in trout. 1835 26


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>