Structural analysis of an acidic polysaccharide secreted by Xanthobacter sp. (ATCC 53272).

The structure of an acidic polysaccharide secreted by a Xanthobacter sp. has been investigated by glycosyl-residue and glycosyl-linkage composition analyses, and the characterization of oligoglycosyl fragments of the polysaccharide has been carried out by chemical analyses, 1H-n.m.r. spectroscopy, fast-atom bombardment mass spectrometry, and electron-impact mass spectrometry. The polysaccharide, which contains O-acetyl groups (approximately 5%) that have not been located, has the tetraglycosyl repeating unit 1 and belongs to a group of structurally related polysaccharides synthesized by both Alcaligenes and Pseudomonas species.

Electron microprobe X-ray analysis of polyphosphate granules in Plesiomonas shigelloides.

Electron-dense inclusion bodies were found in most Plesiomonas shigelloides cells, regardless of the incubation time. At the 4-hr incubation period, the size of inclusion bodies was distributed in the range of 50 to 150 nm in diameter, and at the logarithmic phase of growth it increased up to a size visible by light microscope. By an electron microprobe X-ray analysis, phosphorus, potassium, and magnesium were detected in the inclusion bodies which confirms the assumption of Pastian and Bromel (Appl. Environ. Microbiol. 47: 216 (1984] that the inclusion bodies have a very similar elemental composition to the polyphosphate granules of C. diphtheriae.

Solution structure of 5-keto-D-fructose: relevance to the specificity of hexose kinases.

5-Keto-D-fructose (5KF) is isolated from cultures of Gluconobacter cerinus growing on D-fructose as the sole carbon source. 5KF is a substrate for hexokinase, fructokinase, and several polyol dehydrogenases. 1H and 13C nuclear magnetic resonance studies show that 5KF exists in different forms in anhydrous dimethyl-d6 sulfoxide and D2O. In dimethyl-d6 sulfoxide, 5KF exists as a spirane dimer with linked furanose and pyranose rings, similar to the structure reported for crystalline 5KF [Hassen, L., Hordvik, A., & Hove, R. (1976) J. Chem. Soc., Chem. Commun., 572-. In D2O, 5KF exists predominantly (greater than 95%) in a beta-pyranose form with the 5-keto group hydrated to form a gem-diol. 13C--1H coupling patterns, 13C relaxation measurements, and 13C deuterium-induced differential isotope shifts confirm this structure of 5KF. The phosphorylation of 5KF by fructokinase can be accounted for by an approximately 2% proportion of the beta-furanose form in solution at 25 degrees C. Both the beta-pyranose and beta-furanose forms of 5KF are proposed to be substrates for yeast hexokinase.

Gluconobacters from honey bees.

Fifty-six Gluconobacter strains and one Acetobacter strain were isolated from honey bees and their environment in three different regions in Belgium and identified phenotypically. Polyacrylamide gel electrophoresis of the soluble cell proteins showed that two different types exist within the Gluconobacter isolates: strains from type A were found in samples of the three regions, whereas strains from type B were only isolated in two of the three regions. Both types could occur in bees from the same region, from several hives of one bee keeper and from one hive. Strains from type A were almost identical with collection strain G. oxydans subsp. suboxydans NCIB 9018, whereas strains from type B constituted a new protein electrophoretic type within the genus Gluconobacter. Although Gluconobacter is apparently associated with honey bees, it is not known whether it is important or required for the bees or any hive product.

An ornithine-containing lipid isolated from Gluconobacter cerinus.

The three ornithine-containing lipids of Gluconobacter cerinus were isolated from each other. One of the three lipids was postulated as Nalpha-3-hydroxypalmitoylornithine, to the fatty acid moiety of which 2-hydroxy fatty acid is linked by an ester linkage. The 2-hydroxy acid was possibly cis-11, 12-methylene-2-hydroxyoctadecanoate. Such an ornithine-containing lipid was found to be distributed in other acetic acid bacteria.

The amino acid sequence of ferredoxin II from Chlorobium limicola, a photosynthetic green bacterium.

The amino acid sequence of ferredoxin II from the photosynthetic green sulfur-reducing bacterium, Chlorobium limicola, was deduced to be: Ala-His-Arg-Ile-Thr-Glu-Glu-Cys-Thr-Tyr-Cys-Ala-Ala-Cys-Glu-Pro-Glu-Cys-Pro-Val-Asn-Ala-Ile-Ser-Ala-Gly-Asp-Glu-Ile-Tyr-Ile-Val-Asp-Glu-Ser-Val-Cys-Thr-Asp-Cys-Glu-Gly-Tyr-Tyr-Asp-Glu-Pro-Ala-Cys-Val-Ala-Val-Cys-Pro-Val-Asp-Cys-Ile-Ile-Lys-Val. The ferredoxin was shown to consist of 61 amino acids in a single polypeptide chain. The presence of 8 g-atoms of Fe and 8 mol of sulfide led to a calculated molecular weight of 7289. In constract to the ferredoxin I from C. limicola, ferredoxin II contains basic amino acids in positions 2 and 3 and 60 from the NH(2)-terminal end of the protein. The sequences of all the various ferredoxins from photosynthetic bacteria reported to date are compared with one another.

Identification and grouping of bacteria by numerical analysis of their electrophoretic protein patterns.

Improved methods for the identification and grouping of bacteria by polyacrylamide gel electrophoresis of soluble proteins are described. Electrophoretic protein patterns were obtained in rigorously standardized comditions. The results were much more reproducible than any described previously. Some of the factors affecting reproducibility were; growth conditions, time and speed of centrifugation of extracts, and conditions of gel electrophoresis. Protein patterns were compared by computing correlation coefficients from normalized densitometric tracings and clustering the strains by the unweighted average pair group method. As model systems, both Agrobacterium and Zymomonas were used because of differences in the sharpness of the peaks. The methodwas applied to 42 Agrobacterium strains. The agreement with the results of clustering by either phenotypic tests or DNA:DNA hybridization was excellent. Computerized comparisons of electrophoretic protein patterns can be a fast, easy and powerful tool for classification and identification of bacteria.