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51.
The complete genome sequence of Bacillus licheniformis DSM13, an organism with great industrial potential 总被引:8,自引:0,他引:8
Veith B Herzberg C Steckel S Feesche J Maurer KH Ehrenreich P Bäumer S Henne A Liesegang H Merkl R Ehrenreich A Gottschalk G 《Journal of molecular microbiology and biotechnology》2004,7(4):204-211
The genome of Bacillus licheniformis DSM13 consists of a single chromosome that has a size of 4,222,748 base pairs. The average G+C ratio is 46.2%. 4,286 open reading frames, 72 tRNA genes, 7 rRNA operons and 20 transposase genes were identified. The genome shows a marked co-linearity with Bacillus subtilis but contains defined inserted regions that can be identified at the sequence as well as at the functional level. B. licheniformis DSM13 has a well-conserved secretory system, no polyketide biosynthesis, but is able to form the lipopeptide lichenysin. From the further analysis of the genome sequence, we identified conserved regulatory DNA motives, the occurrence of the glyoxylate bypass and the presence of anaerobic ribonucleotide reductase explaining that B. licheniformis is able to grow on acetate and 2,3-butanediol as well as anaerobically on glucose. Many new genes of potential interest for biotechnological applications were found in B. licheniformis; candidates include proteases, pectate lyases, lipases and various polysaccharide degrading enzymes. 相似文献
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Quentmeier A Hellwig P Bardischewsky F Grelle G Kraft R Friedrich CG 《Biochemical and biophysical research communications》2003,312(4):1011-1018
The central protein of the sulfur-oxidizing enzyme system of Paracoccus pantotrophus, SoxYZ, formed complexes with subunits associated and covalently bound. In denaturing SDS-polyacrylamide gel electrophoresis (PAGE) SoxY migrated at 12 and SoxZ at 16kDa. SDS-PAGE of homogeneous SoxYZ without reductant separated dimeric complexes of 25, 29, and 32kDa identified by the N-terminal amino acid sequences as SoxY-Y, SoxY-Z, and SoxZ-Z, and subunit cleavage by reduction suggested their linkage via protein disulfide bonds. SoxYZ was reversibly redox active between -0.25 and 0.2V, as monitored by a combined electrochemical and FTIR spectroscopic approach. The dimanganese SoxB protein (58.611Da) converted the covalently linked heterodimer SoxY-Z to SoxYZ with associated subunits which in turn aggregated to the heterotetramer Sox(YZ)(2). This reaction depended on time and the SoxB concentration, and demonstrated the interaction of these two Sox proteins. 相似文献
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ABCA10, a novel cholesterol-regulated ABCA6-like ABC transporter 总被引:2,自引:0,他引:2
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The temporal and spatial distribution of cysteine proteinases (CPRs) was analyzed immunologically and by in situ hybridization to identify the CPRs involved in the initiation of storage-globulin degradation in embryonic axes and cotyledons
of germinating vetch (Vicia sativa L.). At the start of germination several CPRs were found in protein bodies in which they might have been stored in the mature
seeds. Cysteine proteinase 1 was predominantly found in organs like the radicle, which first start to grow during germination.
Cysteine proteinase 2 was also present at the start of germination but displayed a less-specific histological pattern. Proteinase
B was involved in the globulin degradation of vetch cotyledons as well. The histological pattern of CPRs followed the distribution
of their corresponding mRNAs. The latter were usually detected earlier than the CPRs but the in situ hybridization signals were histologically not as restricted as the immunosignals. Proteolytic activity started in the radicle
of the embryonic axis early during germination. Within 24 h after imbibition it had also spread throughout the whole shoot.
At the end of germination, newly synthesized CPRs might have supplemented the early detectable CPRs in the axis. In the cotyledons,
only the abaxial epidermis and the procambial strands showed proteinase localization during germination. Both CPR1 and CPR2,
as well as the less common proteinase B, might have been present as stored proteinases. Three days after imbibition, proteolytic
activity had proceeded from the cotyledonary epidermis towards the vascular strands deeper inside the cotyledons. The histochemical
detection of the CPRs was in accordance with the previously described histological pattern of globulin mobilization in germinating
vetch [Tiedemann J, et al. (2000)]. A similar link between the distribution of CPRs and globulin degradation was found in
germinating seeds of Phaseolus vulgaris L. The coincidence of the histological patterns of globulin breakdown with that of the CPRs indicates that at least CPR1,
CPR2 and proteinase B are responsible for bulk globulin mobilization in the seeds of the two legumes.
Received: 14 February 2000 / Accepted: 16 August 2000 相似文献
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Kammerl MC Richthammer W Kurtz A Krämer BK 《American journal of physiology. Regulatory, integrative and comparative physiology》2002,282(6):R1613-R1617
Salt restriction leads to parallel increases of renin, cyclooxygenase-2 (COX-2), and neuronal nitric oxide synthase (nNOS) gene expression in the juxtaglomerular apparatus of rat kidneys. Because the upregulation of these genes is strongly enhanced if salt restriction is combined with inhibition of the renin-angiotensin-aldosterone system, our study aimed to find out whether the juxtaglomerular expressions of renin, COX-2, and nNOS are subject to a common direct negative feedback control by ANG II. For this purpose, male Sprague-Dawley rats were fed a low-salt diet (0.02% wt/wt) with or without additional treatment with the ANG I-converting enzyme (ACE) inhibitor ramipril (10 mg x kg body wt(-1) x day(-1)) for 1 wk, and renocortical renin, COX-2, and nNOS mRNAs were assayed. To narrow down possible indirect effects of the ACE inhibitor that may result from insufficient aldosterone production, the animals received mineralocorticoid substitution with fludrocortisone (6 mg. kg body wt(-1) x day(-1)). Thus mineralocorticoid substitution prevented the fall of systolic blood pressure and of glomerular filtration induced by ramipril in rats on low-salt diet. Although fludrocortisone had no effect on basal renin, COX-2, and nNOS mRNA, it clearly attenuated the threefold increases of both renin and COX-2 mRNA in response to low-salt diet. In rats on low-salt diet, ramipril further increased renin mRNA ninefold, COX-2 mRNA fourfold, and nNOS 2.5-fold in the absence of fludrocortisone. In the presence of fludrocortisone, ramipril increased renin mRNA 10-fold, COX-2 mRNA 2.5-fold, and nNOS mRNA 2.5-fold. These data indicate that mineralocorticoid substitution lowers the overall expression of juxtaglomerular renin and COX-2 during low-salt intake and attenuates a further rise of COX-2 expression by ACE inhibition, but it does not change the stimulatory effect of ACE inhibition on renin and nNOS expression. We conclude that the expression of renin, COX-2, and nNOS in the juxtaglomerular apparatus during low-salt diet is markedly limited by a direct feedback inhibition through ANG II. 相似文献
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