Arthrobacter sulfur

Several natural polysaccharides are esterified with sulfuric or phosphoric acid. Sulfated bacterial polysaccharides are not, however, very common. One example is a polysaccharide from an Arthrobacter species, which is most probably linked to the proteoglycan and contains sulfated D-galactopy-ranosyl residues. An extracellular polysaccharide from a Phormidium spe-... 

The metabolism of 2-methylquinoline in Arthrobacter sp. strain Rii 61a is comparable, with introduction of oxygen at C4 (Hund et al. 1990). The enzymes (oxidoreductases) that introduce oxygen into the azaarene rings in Rhodococcus sp. strain Bl, Arthrobacter sp. strain Rii61a, and Pseudomonas putida strain 86 are virtually identical and, like those already noted have molecular masses of 300-320 kDa and contain Mo, Fe, FAD, and acid-labile sulfur (De Beyer and Lingens... 

The degradation of nicotine has been examined extensively in Arthrobacter nicotinovorans (oxydans) in which it is mediated by a plasmid (Brandsch et al. 1982 Schenk et al. 1998). In strain P34, the hrst metabolite was 6-hydroxynicotine, and experiments with 02 and H2 0 showed that the oxygen in the hydroxyl group was derived from H2O (Hochstein and Dalton 1965). Nicotine dehydrogenase has a molecular mass of 120,000 and contains FAD, Mo, Fe, and acid-labile sulfur (Freudenberg et al. 1988). Degradation involves a series of reactions ... 

The mining of massive sulfur deposits and the exposure of the element to air and water permits the development of populations of sulfur-oxidizing bacteria, with concomitant formation of acidity and sulfate ions. The occurrence of T. thiooxidans and T. thioparus in the Rozdol deposit in Russia has been described by Karavaiko (1959 1961). Similar events can occur during the industrial uss e of elemental sulfur and the amenability of sulfur to bacterial oxidation has been widely exploited agriculturally for modification of soil acidity, supply of sulfate ion and for in situ solubilisation of rock phosphate (Starkey, 1950 Gleen and Quastel, 1953 Vitolins and Swaby, 1969). While most attention has been focussed on chemolitho-trophic thiobacilli, such as T. thiooxidans and T. thioparus, an ability to oxidise elemental sulfur has been shown to be possessed by a number of heterotrophs such as the 35 species of Streptomyces examined by Yagi et al. (1971) and Arthrobacter (Ehrlich, 1962). 

Another purified enzyme preparation which produces laminaripentaose from insoluble laminarin and from heat-treated pachyman is produced by a strain of Arthrobacter luteus (100,101,102) when grown on yeast cells or / -(1 —>3)-glucan. The enzyme, which was named Zymolase (also referred to as Zymolyase) appeared to be homogeneous by electrophoresis in a Tiselius apparatus and by ultracentrifugation. The molecular weight of the enzyme was estimated from ultracentrifugation to be ca. 20,500. The optimum pH for lysis of viable yeast cells was 7.5. The optimum temperature was 35°C. The optimum pH for heat-treated pachyman hydrolysis was 6.5, and the optimum temperature was 45°C. A Lineweaver-Burk plot with heat-treated pachyman yielded a Km value of 0.04% when the solubilized carbohydrate was assayed by the phenol-sulfuric acid method. Zymolase lost all its activity after incubation at 60°C for 5 min. 

Arthrobacter, Bacillus, Micrococcus, Pseudomonas, Mycobacterium Colorless sulfur bacteria Thiobacillus... 

A variety of organic sulfur compounds, in addition to DBT, were shown to be substrates for desulfurization by IGTS8, including thianthrene, phenyl sulfoxide, trithiane, and benzyldisulfide. In contrast, IGTS8 could not metabolize thianaph-thene, phenyl disulfide, and 2-thiophene-carboxylic acid (50), a similar substrate profile as the Arthrobacter isolate previously described by Knecht. A number of other bacteria have subsequently been isolated that use an analogous pathway and have similar substrate ranges (51-56). 

Enzyme adsorption by cellulose films was observed by several methods, including XPS, and was followed by enzymic degradation of the films. Silicate glass surfaces were found to be depleted in Fe and Al as a result of exposure to Bacillus sp. XPS revealed that reduced sulfur forms in aqueous solutions of coal-derived products were not oxidized by dibenzothiophene-degrading bacteria, supporting the indication that extensive degradation of the carbon structure was concurrent with the loss of sulfur. In the context of the extraction of iron from a hornblende by Arthrobacter sp., the formation of siderophore-Fe surface complexes was examined by an XPS study of Fe with and without the siderophore on gold surfaces, and of the siderophore on hornblende crystal surfaces. ... 

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