Oxidation of acyclic terpenoids by Corynebacterium sp

Squalene analogs such as lycopersene, geranylfarnesyl, digeranyl, and 2-hydroxy-2,3-dihydrosqualene and terpene alcohol derivatives such as farnesyl benzyl ether, farnesyl pivalate, geranylgeranyl pivalate, geranyl pivalate, and geranyl benzyl ether were oxidized by Corynebacterium sp. strain SY-79, which was isolated from soil by using squalene as a carbon source. Lycopersene and geranylfarnesyl gave no major product. Digeranyl, geranyl benzyl ether, and geranyl pivalate gave terminal oxidation products, and 2-hydroxy-2,3-dihydrosqualene, farnesyl benzyl ether, farnesyl pivalate, and geranylgeranyl pivalate were degraded to give lower molecular carboxylic acids. Strain SY-79 showed promising oxidative activities toward acyclic terpenes, although the metabolites obtained were variable, depending upon the structure of the substrate.     

Addition of water to acyclic terpenoids by Fusarium solani

Summary Fusarium solani strains DSM 62416 and 62413 were found to hydrate trans-nerolidol or geranylacetone at the inner double bond. The stereochemical requirements for the substrate are rather narrow. Only E-configurated double bonds were accepted by the hydratases and no hydration was observed at the terminal isoprenyl unit of various substrates. The hydratases differ in their substrate specificity. While trans-nerolidol is accepted by the hydratase of strain DSM 62416 and geranylacetone is not, the contrary is found for the hydratase of strain DSM 62413. Higher yields of hydrated products under anaerobic conditions revealed that oxygen is not required as a cofactor.Dedicated to Professor Dr. Klaus Kieslich on the occasion of this 60th birthday     

Microbial Transformation of Squalene: Terminal Methyl Group Oxidation by Corynebacterium sp

Corynebacterium sp. strain SY-79 was isolated from soil, using squalene as a carbon source. Microbiological properties of this bacterium are described. The metabolic product of this bacterium from squalene was identified as 2,6,10,15,19, 23-hexamethyl-2,6,10,14,18,22-tetracosahexaenedioic acid (squalenedioic acid).     

Production of Polyalcohol by a Corynebacterium sp.

A gluconate-utilizing strain of Corynebacterium was found to be capable of utilizing aldopentoses and producing corresponding pentitols when pentoses were added to the medium containing gluconate as a carbon source during the cultivation of the organism.

Pentitols produced from d-xylose, l-arabinose, and d-ribose were isolated from the cultured medium and identified as xylitol, l-arabitol, and ribitol, respectively.

The pentitol production was significantly influenced by the concentration of gluconate in the initial medium and that of pentose added to the medium during the cultivation.

The amount of xylitol, l-arabitol, and ribitol reached 69 mg/ml, 60 mg/ml, and 32 mg/ml, respectively, after 14 days of incubation when pentoses were added to the medium containing 9.6% potassium gluconate to give a final concentration of 150 mg/ml.     

Catabolism of citronellol and related acyclic terpenoids in pseudomonads

Terpenes are a huge group of natural compounds characterised by their predominantly pleasant smell. They are built up by isoprene units in cyclic or acyclic form and can be functionalised by carbonyl, hydroxyl or carboxyl groups and by presence of additional carbon–carbon double bonds (terpenoids). Currently, much more than 10,000 terpenoid compounds are known, and many thereof are present in different iso- and stereoforms. Terpenoids are secondary metabolites and can have important biological functions in living organisms. In many cases, the biological functions of terpenoids are not known at all. Nevertheless, terpenoids are used in large quantities as perfumes and aroma compounds for food additives. Terpenoids can be also precursors and building blocks for synthesis of complex chiral compounds in chemical and pharmaceutical industry. Unfortunately, only few terpenoids are available in large quantities at reasonable costs. Therefore, characterisation of suited biocatalysts specific for terpenoid compounds and development of biotransformation processes of abundant terpenoids to commercially interesting derivates becomes more and more important. This minireview summarises knowledge on catabolic pathways and biotransformations of acyclic monoterpenes that have received only little attention. Terpenoids with 20 or more carbon atoms are not a subject of this study.     

Desulfurization of dibenzothiophene by Corynebacterium sp. strain SY1.

Strain SY1, identified as a Corynebacterium sp., was isolated on the basis of the ability to utilize dibenzothiophene (DBT) as a sole source of sulfur. Strain SY1 could utilize a wide range of organic and inorganic sulfur compounds, such as DBT sulfone, dimethyl sulfide, dimethyl sulfoxide, dimethyl sulfone, CS2, FeS2, and even elemental sulfur. Strain SY1 metabolized DBT to dibenzothiophene-5-oxide, DBT sulfone, and 2-hydroxybiphenyl, which was subsequently nitrated to produce at least two different hydroxynitrobiphenyls during cultivation. These metabolites were separated by silica gel column chromatography and identified by nuclear magnetic resonance, UV, and mass spectral techniques. Resting cells of SY1 desulfurized toluenesulfonic acid and released sulfite anion. On the basis of these results, a new DBT degradation pathway is proposed.     

Desulfurization of dibenzothiophene by Corynebacterium sp. strain SY1.

Strain SY1, identified as a Corynebacterium sp., was isolated on the basis of the ability to utilize dibenzothiophene (DBT) as a sole source of sulfur. Strain SY1 could utilize a wide range of organic and inorganic sulfur compounds, such as DBT sulfone, dimethyl sulfide, dimethyl sulfoxide, dimethyl sulfone, CS2, FeS2, and even elemental sulfur. Strain SY1 metabolized DBT to dibenzothiophene-5-oxide, DBT sulfone, and 2-hydroxybiphenyl, which was subsequently nitrated to produce at least two different hydroxynitrobiphenyls during cultivation. These metabolites were separated by silica gel column chromatography and identified by nuclear magnetic resonance, UV, and mass spectral techniques. Resting cells of SY1 desulfurized toluenesulfonic acid and released sulfite anion. On the basis of these results, a new DBT degradation pathway is proposed.     

Biotransformation of acyclic monoterpenoids by Debaryomyces sp., Kluyveromyces sp., and Pichia sp. strains of environmental origin

Sixty yeast strains, which belong to 32 species of the genera Debaryomyces, Kluyveromyces, and Pichia, and which were isolated from plant-, soil- or insect-associated habitats, were screened for their ability to biotransform the acyclic monoterpenes geraniol and nerol. The aptitude to convert both compounds (from 2.6 to 30.6, and from 2.7 to 29.1%/g cell DW (=dry weight), resp.) was apparently a broad distributed character in such yeasts. Depending upon the substrate used, the production of linalool, alpha-terpineol, beta-myrcene, D-limonene, (E)-beta-ocimene, (Z)-beta-ocimene, or carene was observed. Linalool was the main product obtained from geraniol, whereas linalool and alpha-terpineol were the main products obtained through the conversion of nerol. Yet, differently from nerol, the aptitude to exhibit high bioconversion yields of geraniol to linalool was an apparently genus-related character, whereas the ability to produce other monoterpenes was a both genus- and habitat-related character. The possible pathways of bioconversion of geraniol or nerol to their derivatives were proposed/discussed.     

Carbohydrates Oxidation by Pseudomonas albosesamae nov. sp.

An oxidation product of glucose, gluconate and 2-ketogluconate by Pseudomonas albosesamae was isolated and examined for its chemical structure. Shaking culture is available for the high yield production. Paper chromatographic analysis of fermented broth for the product gives one spot as “an reducing acid.” The acid was isolated as the unstable powder of calcium salt by methanol precipitation. On periodate oxidation, oxalic and glycolic acids were formed, but formaldehyde was hardly detected. On Ruff’s oxidation of the reduced product prepared by sodium borohydrate or catalytic reduction, D-arabinose and a small amount of L-xylose were detected. On catalytic reduction using Raney nickel, 2-ketogluconic acid was isolated as the main reductant. Bis-2, 4-dinitrophenylhydrazone of the product was obtained as analytically pure yellow needle crystals, m.p. dec. 156~157°C, 5+57.0, pyridine, 1 dm. From the above results, the product was certified to be 2,5-diketogluconic acid.     

Carbohydrates Oxidation by Pseudomonas albosesamae nov. sp.

Taxonomic behaviors of a newly isolated bacterium which produces 2,5-diketogluconic acid in high yield were examined in this paper. The bacterium was isolated from sesame seed. It is aerobic, rod-shaped bacilli (0.6~0.8 × 1.0~3.0 microns) with rounded ends. It occurs singly or as a small mass and shows motility with a polar flagellum. Gram staining and acid-fast staining are both negative. Endospore and capsule are not observed. It does not possess photosynthetic and usual pigments the cell. Glucose and other sugars are attacked with acid production, but no gas formation. Polysaccharides and sucrose are not attacked. This bacterium does not produce acetic acid from ethanol. The above behaviors and other physiological properties which are described in the text lead to the conclusion that the bacterium is a new species situated in the genus Pseudomonas. So, it was named Pseudomonas albosesamae, nov. sp. (Wakisaka) in relation with its isolated origin.     

Proposal of Corynebacterium propinquum sp. nov. for Corynebacterium group ANF-3 strains

Abstract Chemotaxonomic and genomic studies were performed on seven Corynebacterium group ANF-3 strains isolated from human sources. All these strains possess cell wall component type IV ( meso -diaminopimelic acid, arabinose and galactose), corynemycolic acids and a G+C content of DNA of 57 to 59 mol%. These results confirm that they can be placed in the genus Corynebacterium . Six of these strains were found to constitute a tight hybridization group distinct from named Corynebacterium species or related organisms. This genomic group constitutes a new species which can be identified within the genus Corynebacterium by ribotyping or phenotypic tests and for which the name Corynebacterium propinquum is proposed. The type strain is strain B 77159 (= Collection of the Institut Pasteur CIP 103792).     

Purification and some properties of guanidinoacetate amidinohydrolase produced by Corynebacterium sp.

Guanidinoacetate amidinohydrolase (EC 3.5.3.2) was purified from Cornebacterium sp. grown in a medium supplemented with guanidinoacetate, and some of its properties were investigated.The molecular weight of the enzyme was estimated to be 150,000 by gel filtration. SDS-polyacrylamide gel electrophoresis showed a single subunit component with a molecular weight of 38,000, suggesting that the enzyme is composed of four identical subunits. The isoelectric point of the enzyme was pH 5.8.The enzyme showed optimum activity at pH 9.0–9.5 and was stable at pH 6.0–10.5. 3-Guanidinopropionate and 4-guanidinobutyrate were respectively hydrolyzed 32% and 5% as fast as guanidinoacetate. The apparent K_m for guanidinoacetate was 16 mM. Incubation of the enzyme by o-phenanthroline or 8-hydroxyquinoline resulted in almost complete inactivation. The activity of the inactivated enzyme was restored by incubation with Zn²⁺. p-Chloromercuribenzoic acid and iodine effectively inhibited the enzyme activity. Glycine was a competitive inhibitor, and n-alkyl amines such as n-octylamine, n-decylamine and n-dodecylamine were uncompetitive inhibitors.     

Oxidation of C1 compounds by Pseudomonas sp. MS

Pseudomonas sp. MS is capable of growth on a number of compounds containing only C₁ groups. They include trimethylsulphonium salts, methylamine, dimethylamine and trimethylamine. Although formaldehyde and formate will not support growth they are rapidly oxidized by intact cells. Methanol neither supports growth nor is oxidized. A particulate fraction of the cell oxidizes methylamine to carbon dioxide in the absence of any external electron acceptor. Formaldehyde and formate are more slowly oxidized to carbon dioxide by the particulate fraction, although they do not appear to be free intermediates in the oxidation of methylamine. Soluble NAD-linked formaldehyde dehydrogenase and formate dehydrogenase are also present. The particulate methylamine oxidase is induced by growth on methylamine, dimethylamine and trimethylamine, whereas the soluble formaldehyde dehydrogenase and formate dehydrogenase are induced by trimethylsulphonium nitrate as well as the aforementioned amines.     

Genome sequence and description of Corynebacterium ihumii sp. nov.

Corynebacterium ihumii strain GD7^T sp. nov. is proposed as the type strain of a new species, which belongs to the family Corynebacteriaceae of the class Actinobacteria. This strain was isolated from the fecal flora of a 62 year-old male patient, as a part of the culturomics study. Corynebacterium ihumii is a Gram positive, facultativly anaerobic, nonsporulating bacillus. Here, we describe the features of this organism, together with the high quality draft genome sequence, annotation and the comparison with other member of the genus Corynebacteria. C. ihumii genome is 2,232,265 bp long (one chromosome but no plasmid) containing 2,125 protein-coding and 53 RNA genes, including 4 rRNA genes. The whole-genome shotgun sequence of Corynebacterium ihumii strain GD7^T sp. nov has been deposited in EMBL under accession number GCA_000403725.     

Oxidation of nitric oxide by a new heterotrophic Pseudomonas sp.

A new bacterial strain isolated from soil consumed nitric oxide (NO) under oxic conditions by oxidation to nitrate. Phenotypic and phylogenetic characterization of the new strain PS88 showed that it represents a previously unknown species of the genus Pseudomonas, closely related to Pseudomonas fluorescens and Pseudomonas putida. The heterotrophic, obligately aerobic strain PS88 was not able to denitrify or nitrify; however, strain PS88 oxidized NO to nitrate. NO was not reduced to nitrous oxide (N₂O). Nitrogen dioxide (NO₂) and nitrite (NO₂ ^–) as possible intermediates of NO oxidation to nitrate (NO₃ ^–) could not be detected. NO oxidation was inhibited under anoxic conditions and by high osmolarity, but not by nitrite. NO oxidation activity was inhibited by addition of formaldehyde, HgCl₂, and antimycin, and by autoclaving or disintegrating the cells, indicating that the process was enzyme-mediated. However, the mechanism remains unclear. A stepwise oxidation at a metalloenzyme and a radical mechanism are discussed. NO oxidation in strain PS88 seems to be a detoxification or a co-oxidation mechanism, rather than an energy-yielding process. Received: 15 November 1995 / Accepted: 24 February 1996     

Characterisation of 2,5-diketo-D-gluconic acid reductase from Corynebacterium sp.

Summary 2,5-diketo-D-gluconic acid reductase, that converts 2,5-diketo-D-gluconic acid into 2-keto-L-gulonic acid (the direct precursor of vitamin C) was extracted and purified from Corynebacterium sp.. The enzyme was characterised in terms of kinetic parameters, molecular weight and isoelectric point. Enzyme stability at different operating temperatures was investigated, as well.     

Purification and characterization of membrane-bound endoglycoceramidase from Corynebacterium sp.

Endoglycoceramidase catalyzes the hydrolysis of the linkage between oligosaccharides and ceramides of various glycosphingolipids. We found that a bacterial strain Corynebacterium sp., isolated from soil, produced endoglycoceramidase both intracellularly and extracellularly. The intracellular enzyme bound to the cell membrane was solubilized with 1% Triton X-100 and purified to homogeneity about 170-fold with 60% recovery. The molecular mass of the enzyme was approximately 65 kDa. The enzyme is most active at pH 5.5-6.5 and stable at pH 3.5-8.0. Various neutral and acidic glycosphingolipids were hydrolyzed by the enzyme in the presence of 0.1% Triton X-100. Ganglio- and lacto-type glycosphingolipids were readily hydrolyzed, but globo-type glycosphingolipids were hydrolyzed slowly.