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KL55, KL74, and KL85 capsular polysaccharide (CPS) biosynthesis loci in Acinetobacter baumannii BAL_204, BAL_309, and LUH5543 genomes, respectively, are related and each contains genes for l -Rha p and d -Glc p A synthesis. The CPSs were isolated and studied by sugar analysis, Smith degradation, and 1H and 13C NMR spectroscopy. The K55 and K74 CPSs are built up of branched octasaccharide repeats (K units) containing one residue each of d -Glc p A and d -Glc p NAc and six residues of l -Rha p. The K55 unit differs from the K74 unit in the linkage between D-Glc p A and an l -Rha p residue in the K unit (1 → 3 versus 1 → 2) and linkage between K units. However, most K units in the isolated K74 CPS were modified by β-elimination of a side-chain α- l -Rha p -(1 → 3)-α- l -Rha p disaccharide from position 4 of GlcA to give 4-deoxy- l - threo -hex-4-enuronic acid (1:~3 ratio of intact and modified units). The K85 CPS has a branched heptasaccharide K unit similar to the K74 unit but with one fewer α- l -Rha p residue in the side chain. In contrast to previous findings on A. baumannii CPSs, each K locus includes fewer glycosyltransferase (Gtr) genes than the number required to form all linkages in the K units. Hence, one Gtr appears to be multifunctional catalysing formation of two 1 → 2 and one 1 → 3 linkages between the l -Rha residues. [ABSTRACT FROM AUTHOR]

In this study, we analyze 31 transgenic lines and their respective untransformed background lines to determine the transgene effects on targeted structures including the pectin components rhamnogalacturonan I (RG-I) and homogalacturonan (HG), neutral side chains (galactan/arabinangalactan), acetylation of pectin, and cellulose level. Modification arising from the pectin backbone- or pectin side chain transgenic lines either increased or decreased the HG:RG-I ratio, side chain length, and methyl esterification of pectin in the tuber cell wall. The pectin esterification transgenic line exhibited only limited side effects. The cellulose level-targeting transgenic lines yielded an unexpectedly high HG:RG-I ratio and longer pectic side chains. These results clearly demonstrate that in effects of a transgene are not restricted to the direct activity of the targeted enzyme but have consequences for the structure of the cell wall matrix. Analysis of whole cell wall structure is therefore necessary to assess the complete effect, direct and indirect, of a transgene. [ABSTRACT FROM AUTHOR]

Abstract: The type and amount of anthocyanins in raspberries, and other small fruits, has recently received increased attention. Black raspberry (Rubus occidentalis L.), in particular, has long been recognized as a rich source of anthocyanins and has been the focus of many recent studies examining their potential health benefits. In this study, we characterized a novel anthocyanin profile found in seedlings of two wild black raspberry populations collected from South Dakota, USA. Seedlings from these populations lack pigments glycosylated with rutinoside in their fruit, have elevated levels of cyanidin-3-sambubioside, and contain a small but significant amount of pelargonidin-3-glucoside, a pigment reported only once previously in black raspberry. Affected fruit also have lower than typical total anthocyanins (77.5–134.4mg100mL−1). Based on the available evidence, we believe the plants have a mutation in the gene encoding anthocyanidin-3-glycoside rhamnosyltransferase (3RT), providing a unique opportunity to identify and study one of the major genes in the anthocyanin pathway and its effect on fruit anthocyanins and color. [Copyright &y& Elsevier]

Abstract: A new bacterial strain isolated from activated sludge, identified as Pseudomonas aeruginosa EMS1, produced a biosurfactant when grown on acidified soybean oil as the sole carbon source. An optimum biosurfactant production of 5g/L was obtained with the following medium composition: 2% acidified soybean oil, 0.3% NH4NO3, 0.03% KH2PO4, 0.03% K2HPO4, 0.02% MgSO4 ·7H2O and 0.025% CaCl2 ·2H2O, with shaking at 200rpm for an incubation period of 100h at 30°C. The production of the biosurfactant was found to be a function of cell growth, with maximum production occurring during the exponential phase. Hemolysis of erythrocytes and thin-layer chromatography studies revealed that the secreted biosurfactant was rhamnolipid. To overcome the complex environmental regulation with respect to rhamnolipid biosynthesis, and to replace the opportunistic pathogen P. aeruginosa with a safe industrial strain, attempts were made to achieve rhamnolipid production in a heterologous host, Pseudomonas putida, using molecular cloning of rhlAB rhamnosyltransferase genes with the rhlRI quorum sensing system, assuming that a functional rhamnosyltransferase would catalyze the formation of rhamnosyl-6-hydroxydecanoyl-6-hydroxydecanoate (mono-rhamnolipid) in P. putida. It was shown that rhamnolipid can be produced in the heterologous strain, P. putida, when provided with the rhamnosyltransferase genes. [Copyright &y& Elsevier]