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1.
Genes for the biosynthesis of spinosyns: applications for yield improvement in Saccharopolyspora spinosa 总被引:2,自引:0,他引:2
K Madduri C Waldron P Matsushima M C Broughton K Crawford D J Merlo R H Baltz 《Journal of industrial microbiology & biotechnology》2001,27(6):399-402
Spinosyns A and D are the active ingredients in an insect control agent produced by fermentation of Saccharopolyspora spinosa. Spinosyns are macrolides with a 21-carbon, tetracyclic lactone backbone to which the deoxysugars forosamine and tri-O-methylrhamnose are attached. The spinosyn biosynthesis genes, except for the rhamnose genes, are located in a cluster that
spans 74 kb of the S. spinosa genome. DNA sequence analysis, targeted gene disruptions and bioconversion studies identified five large genes encoding type
I polyketide synthase subunits, and 14 genes involved in sugar biosynthesis, sugar attachment to the polyketide or cross-bridging
of the polyketide. Four rhamnose biosynthetic genes, two of which are also necessary for forosamine biosynthesis, are located
outside the spinosyn gene cluster. Duplication of the spinosyn genes linked to the polyketide synthase genes stimulated the
final step in the biosynthesis — the conversion of the forosamine-less pseudoaglycones to endproducts. Duplication of genes
involved in the early steps of deoxysugar biosynthesis increased spinosyn yield significantly. Journal of Industrial Microbiology & Biotechnology (2001) 27, 399–402.
Received 31 May 2001/ Accepted in revised form 09 July 2001 相似文献
2.
3.
Production of monocyte chemotactic and activating factor (MCAF) by human dermal fibroblasts in response to interleukin 1 or tumor necrosis factor 总被引:16,自引:0,他引:16
C G Larsen C O Zachariae J J Oppenheim K Matsushima 《Biochemical and biophysical research communications》1989,160(3):1403-1408
Normal human dermal fibroblasts rapidly expressed (less than 30 min.) considerable mRNA for monocyte chemotactic and activating factor (MCAF) and released high levels of biological activity in response to interleukin 1 (IL 1) or tumor necrosis factor (TNF). In contrast, cultured normal human keratinocytes did not express MCAF mRNA when stimulated with IL 1 or TNF. These results suggest the important role of dermal fibroblasts, the predominant cells in dermal connective tissue, in the recruitment of monocytes during inflammation. This is the first report of the induction of MCAF by IL 1 or TNF in any cell type. 相似文献
4.
Cloning and sequencing of the cDNA for human monocyte chemotactic and activating factor (MCAF) 总被引:28,自引:0,他引:28
Y Furutani H Nomura M Notake Y Oyamada T Fukui M Yamada C G Larsen J J Oppenheim K Matsushima 《Biochemical and biophysical research communications》1989,159(1):249-255
cDNA clones having a nucleotide sequence encoding a human monocyte chemotactic and activating factor (MCAF) were isolated and sequenced. The amino acid sequence deduced from the nucleotide sequence reveals the primary structure of the MCAF precursor to be composed of a putative signal peptide sequence of 23 amino acid residues and a mature MCAF sequence of 76 amino acid residues. The amino acid sequence of MCAF showed 25-55% homology with other members of an inducible cytokine family, including macrophage inflammatory protein and some putative polypeptide mediators known as JE, LD78, RANTES and TCA-3. This suggests that MCAF is a member of family of factors involved in immune and inflammatory responses. 相似文献
5.
6.
Amylase activity in the saliva, salivary glands, serum, liver (perfused and non perfused) and pancreas was assayed and isoamylases were separated by electrophoresis in these organs using C57BR/cdJ and M. m. molossinus (Kor) mice. Amylase isozymes in the saliva, parotid gland, serum and liver were identical in both strains, respectively. Amylase activity in the liver was lower than that in the serum and liver amylase disappeared almost by perfusion. Major serum amylase was released from the parotid gland in intact animals. 相似文献
7.
K Matsushima T Akahoshi M Yamada Y Furutani J J Oppenheim 《Journal of immunology (Baltimore, Md. : 1950)》1986,136(12):4496-4502
The properties of specific human interleukin 1 (IL 1) receptors on human Epstein Barr virus-transformed B lymphocytes (EBV-B) were studied. Purified human IL 1-beta from a myelomonocytic cell line (THP-1) was labeled with 125I by the Bolton-Hunter method without detectable loss of biological activity. Among four EBV-B cell lines tested, a pre-B cell type (VDS-O) specifically bound the highest amount of 125I-IL 1-beta. Maximal binding was reached within 20 min at 4 degrees C. Scatchard plot analysis of the binding of 125I-IL 1-beta to VDS-O cells yielded a Kd (dissociation constant) of 2.4 to 5.9 X 10(-10) M with 110 to 220 binding (receptor) sites/cell. The binding of 125I-IL 1-beta to VDS-O cells was also inhibited by F(ab)'2 fragments of anti-human IL 1 and recombinant human IL 1-alpha, as well as by unlabeled human IL 1-beta but not by recombinant lymphotoxin, recombinant tumor necrosis factor, or phorbol myristic acid, suggesting that IL 1-alpha and IL 1-beta bind specifically to the same receptor. The m.w. of IL 1 receptor on human EBV-B cells was estimated to be 60,000 by both the chemical cross-linking method and high pressure liquid chromatography (HPLC) gel filtration analysis of receptor extracted from membrane enriched fraction by a non-ionic detergent (CHAPS). The isoelectric point of solubilized human IL 1 receptor was 7.3 on HPLC chromatofocusing. The evidence of existence of IL 1 receptor on human EBV-B cells additionally supports the hypothesis that IL 1 may be an autocrine signal for these cells. 相似文献
8.
K Matsushima J Yodoi Y Tagaya J J Oppenheim 《Journal of immunology (Baltimore, Md. : 1950)》1986,137(10):3183-3188
The regulation of interleukin 1 (IL 1) receptor expression on a human large granular lymphocyte cell line, YT, and fate of internalized 125I-labeled IL 1 beta (125I-IL 1 beta) were studied. YT cells were selected for this study, because this cell line expresses a large number of specific high-affinity receptor for IL 1, responds biologically to exogenously added IL 1 by expressing high-affinity IL 2 receptors, and does not produce IL 1. YT cells constitutively express approximately 7 X 10(3) IL 1 receptors/cell with a Kd approximately 10(-10) M. Neither IL 2, phorbol myristic acid, nor lipopolysaccharide affected the total binding of 125I-IL 1 beta by YT cells. In contrast, the capacity of YT cells to bind 125I-IL 1 beta when incubated at 37 degrees C for 3 to 16 hr with a low dose of purified IL 1 beta (approximately 6 U/ml) was reduced by greater than 80%. The loss of binding capability gradually recovered by 16 hr after removal of IL 1 beta from cultured YT cells. The apparent loss of IL 1 receptor expression was accompanied by the internalization of 125I-IL 1 beta into cells. Acid treatment of YT cells to remove bound 125I-IL 1 beta at 4 degrees C showed that 50% of the 125I-IL 1 beta bound to cells could no longer be recovered after 30 min at 37 degrees C, and this increased to 80% after 3 hr at 37 degrees C. Fractionation of cell extracts on Percoll gradient additionally showed 125I-IL 1 beta to appear intracellularly after receptor binding on plasma membranes, and to be successively transferred to some membranous organelles (d approximately equal to 1.037) through an intermediate density organelle (d approximately equal to 1.050), and to finally end up in lysosomal cell fractions (d approximately equal to 1.05 to 1.08) after approximately 3 hr at 37 degrees C. Only approximately 5% of internalized 125I-IL 1 beta was released into culture media by 6 hr of incubation at 37 degrees C. However, the radioactivity in the TCA soluble fraction of the culture media increased gradually by 6 hr and a lysosomotropic enzyme, ethylamine, significantly inhibited both the transfer of internalized 125I-IL 1 beta to the lysosomal fraction and the degradation of 125I-IL 1 beta. This study represents the first evidence of autoregulation of IL 1 receptors by IL 1 and internalization of IL 1 molecules after binding to receptors.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
9.
M Kinoshita M Okazaki H Kato T Teramoto T Matsushima C Naito H Oka I Hara 《Journal of biochemistry》1984,95(4):1111-1118
A simple and rapid method for the analysis of apolipoproteins in high density lipoprotein (HDL) by high performance liquid chromatography (HPLC) has been developed (Kinoshita et al. (1983) J. Biochem. 94, 615-617). With this method, using a sodium phosphate buffer containing 0.1% sodium dodecyl sulfate (SDS) as an eluent, apolipoproteins can be analyzed from a very small amount of HDL fraction without delipidation using organic solvents. Separation profiles of apolipoproteins by this method were examined using several techniques. The elution pattern monitored by A280 can give precise quantitative as well as qualitative information about size-distribution of apolipoproteins, except for the apo C group. Moreover, separation of apo E from apo A-I was found to be improved by column elongation. 相似文献
10.
A previous study demonstrated the preparation of an antiserum having enough specificity and sensitivity for a radioimmunoassay to determine fragment D-dimer derivatives. Using the antiserum the contents of fragment D-dimer derivatives in the sera of normal subjects and patients were determined. The content in normal subjects was 0.260 +/- 0.07 micrograms/ml (mean +/- SD) an that in patients with elevated levels of FDP ranged from 0.30 to 28 micrograms/ml. The values of fragment D-dimer derivatives and FDP in sera of some patients did not necessarily change in parallel, although there seems to be generally a positive correlation between them. 相似文献