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A liquid-phase mixture synthesis of 18 tripeptides, some of which are analogues of ACE inhibitors, was effectively conducted by using fluorous Fmoc reagents as encoding tags. [ABSTRACT FROM AUTHOR]

The gene, designated AsamyR, encoding a transcriptional activator involved in amylolytic gene expression was isolated from a shoyu koji mold, Aspergillus sojae KBN1340, and characterized. The structural gene comprised 1,951 bp with 2 introns. AsAmyR consisted of 595 amino acid residues possessing a high degree of sequence identity with other Aspergillus AmyRs. The AsamyR gene disruptant showed significantly restricted growth on starch agar plates and produced no detectable s-amylase production in SP medium. The multicopy AsamyR strain exhibited approximately two-fold higher amylase activity when compared to that of the control strain, but the increased rate of the amylase activity was not as high as the copy number of the integrated AsamyR gene. [ABSTRACT FROM AUTHOR]

Aspergillus sojae generally has only one ortholog of the Aspergillus oryzae taa (α-amylase) gene. The AstaaG1 gene from a shoyu koji mold, A. sojae KBN1340, comprised 2,063 bp with eight introns. AsTaaG1 consisted of 498 amino acid residues possessing high identity to other Aspergilli α-amylase sequences. Disruption of the AstaaG1 gene resulted in no detectable a-amylase production in starch medium. Promoter activity of the AstaaG1 gene, monitored by xylanase activity, was upregulated with replacement of the CCAAT-Iike sequence. Site-directed mutation of the CCAAT-Iike sequence increased xylanase production approximately four times higher than that of the wild type. These results clearly demonstrate that the decreased copy number of the taa gene and the low affinity binding sequence to the Hap complex lead to the lower amylolytic activity ofA. sojae compared to that of A. oryzae. [ABSTRACT FROM AUTHOR]

Recombinant glycerol dehydratase of Klebsiella pneumoniae was purified to homogeneity. The subunit composition of the enzyme was most probably α2 β2 γ2 . When (R )- and (S )-propane-1,2-diols were used independently as substrates, the rate with the (R )-enantiomer was 2.5 times faster than that with the (S )-isomer. In contrast to diol dehydratase, an isofunctional enzyme, the affinity of the enzyme for the (S )-isomer was essentially the same or only slightly higher than that for the (R )-isomer (K m(R ) /K m(S ) = 1.5). The crystal structure of glycerol dehydratase in complex with cyanocobalamin and propane-1,2-diol was determined at 2.1 Å resolution. The enzyme exists as a dimer of the αβγ heterotrimer. Cobalamin is bound at the interface between the α and β subunits in the so-called ‘base-on’ mode with 5,6-dimethylbenzimidazole of the nucleotide moiety coordinating to the cobalt atom. The electron density of the cyano group was almost unobservable, suggesting that the cyanocobalamin was reduced to cob(II)alamin by X-ray irradiation. The active site is in a (β/α)8 barrel that was formed by a central region of the α subunit. The substrate propane-1,2-diol and essential cofactor K+ are bound inside the (β/α)8 barrel above the corrin ring of cobalamin. K+ is hepta-coordinated by the two hydroxyls of the substrate and five oxygen atoms from the active-site residues. These structural features are quite similar to those of diol dehydratase. A closer contact between the α and β subunits in glycerol dehydratase may be reminiscent of the higher affinity of the enzyme for adenosylcobalamin than that of diol dehydratase. Although racemic propane-1,2-diol was used for crystallization, the substrate bound to glycerol dehydratase was assigned to the (R )-isomer. This is in clear... [ABSTRACT FROM AUTHOR]

The article presents a study which introduced a super clean gasoline production from gas to liquid (GTL) synthetic oil using hydroprocessing. The gasoline derived from GTL synthetic oil has outstanding gasoline properties such as being sulfur-free, aroma-free and olefin-free. GTL synthetic oil is used as a feedstock.

Mouse 2n (lacZ-) <--> 4n (lacZ+) aggregation chimeras were examined 5 or 10 days after uterine transfer to test the potential of 4n cells to contribute to embryonic tissues. Recovered embryos corresponded to embryonic day 7.5 approximately 8.0 and 12.5, respectively. Ten days after transfer, 4n cells were never detected, as reported earlier, in embryonic tissues of chimeras produced by the standard procedure in which one 2n embryo at the8-cell stage is aggregated with a4n embryo at the4-cell stage. However, beta-gal positive cells were present in embryonic tissues, though in a low number, in chimeras produced by a 2n and a 4n embryo at the 4-cell stage. Similar results were obtained when one 2n embryo atthe 8-cell stage was aggregated with two 4n embryos atthe 4-cell stage. beta-gal positive cells were found in the heart, liver, skin and intestinal epithelium. The majority of chimeras 5 days after uterine transfer retained beta-gal positive cells in embryonic tissues. The complete lack of 4n cell contribution to chimeras produced by the standard procedure is therefore attributed to the initial low proportion of 4n cells allocated to epiblast and their severe elimination from embryonic tissues.