Microbial degradation of linseed oil-based elastomer and subsequent accumulation of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) copolymer.

The microbial synthesis of environment-friendly poly(3-hydroxybutyrate--co-3-hydroxyvalerate), PHBV, has been performed by using an alkaliphilic microorganism, Alkaliphilus oremlandii OhILAs strain (GenBank Accession number NR_043674.1), at pH 8 and at a temperature of 30-32 °C through the biodegradation of linseed oil-based elastomer. The yield of the copolymer on dry cell weight basis is 90 %. The elastomers used for the biodegradation have been synthesized by cationic polymerization technique. The yield of the PHBV copolymer also varies with the variation of linseed oil content (30-60 %) in the elastomer. Spectroscopic characterization ((1)H NMR and FTIR) of the accumulated product through biodegradation of linseed oil-based elastomers indicates that the accumulated product is a PHBV copolymer consisting of 13.85 mol% of 3-hydroxyvalerate unit. The differential scanning calorimetry (DSC) results indicate a decrease in the melting (T m) and glass transition temperature (T g) of PHBV copolymer with an increase in the content of linseed oil in the elastomer, which is used for the biodegradation. The gel permeation chromatography (GPC) results indicate that the weight average molecular weight (M w) of PHBV copolymer decreases with an increasing concentration of linseed oil in the elastomer. The surface morphology of the elastomer before and after biodegradation is observed under scanning electron microscope (SEM) and atomic force microscope (AFM); these results indicate about porous morphology of the biodegraded elastomer.

Cloning, expression and characterization of a novel thermophilic polygalacturonase from Caldicellulosiruptor bescii DSM 6725.

We cloned the gene ACM61449 from anaerobic, thermophilic Caldicellulosiruptor bescii, and expressed it in Escherichia coli origami (DE3). After purification through thermal treatment and Ni-NTA agarose column extraction, we characterized the properties of the recombinant protein (CbPelA). The optimal temperature and pH of the protein were 72 °C and 5.2, respectively. CbPelA demonstrated high thermal-stability, with a half-life of 14 h at 70 °C. CbPelA also showed very high activity for polygalacturonic acid (PGA), and released monogalacturonic acid as its sole product. The Vmax and Km of CbPelA were 384.6 U·mg⁻¹ and 0.31 mg·mL⁻¹, respectively. CbPelA was also able to hydrolyze methylated pectin (48% and 10% relative activity on 20%-34% and 85% methylated pectin, respectively). The high thermo-activity and methylated pectin hydrolization activity of CbPelA suggest that it has potential applications in the food and textile industry.

Pullulanibacillus uraniitolerans sp. nov., an acidophilic, U(VI)-resistant species isolated from an acid uranium mill tailing effluent and emended description of the genus Pullulanibacillus.

Two Gram-positive-staining, rod-shaped, endospore-forming isolates (UG-2(T) and UG-3), with an optimum growth temperature of around 37 °C and an optimum pH for growth of about 4, were recovered from an acidic effluent of the uranium mill tailing at Urgeiriça in Central Portugal. On the basis of 16S rRNA gene sequence similarity, the strains belonged to the family Sporolactobacillaceae and were closely related to Pullulanibacillus naganoensis ATCC 53909(T) (97.9 %). Unlike P. naganoensis, strains UG-2(T) and UG-3 grew in medium containing up to 5000 p.p.m. U(VI) but did not hydrolyse pullulan. Chemotaxonomic data also supported the affiliation of strains UG-2(T) and UG-3 to the genus Pullulanibacillus. Physiological and biochemical tests along with fatty acid composition allowed differentiation of strains UG-2(T) and UG-3 from P. naganoensis. It is suggested that strains UG-2(T) and UG-3 represent a novel species, for which the name Pullulanibacillus uraniitolerans is proposed; the type strain is UG-2(T) (=DSM 19429(T) = LMG 24205(T)). An emended description of the genus Pullulanibacillus is also proposed.

Tumebacillus ginsengisoli sp. nov., isolated from soil of a ginseng field.

A gram-reaction-positive, rod-shaped, spore-forming bacterium, designated Gsoil 1105(T), was isolated from soil of a ginseng field in Pocheon Province in South Korea and characterized in order to determine its taxonomic position. Comparative analysis of the 16S rRNA gene sequence showed that the isolate belongs to the order Bacillales, showing the highest level of sequence similarity with respect to Tumebacillus permanentifrigoris Eur1 9.5(T) (94.6 %). The phylogenetic distances from other described species with validly published names within the order Bacillales were greater than 9.0 %. Strain Gsoil 1105(T) had a genomic DNA G+C content of 55.6 mol% and menaquinone 7 (MK-7) as the major respiratory quinone. The major fatty acids were iso-C(15 : 0) and anteiso-C(15 : 0). On the basis of its phenotypic properties and phylogenetic distinctiveness, strain Gsoil 1105(T) represents a novel species of the genus Tumebacillus, for which the name Tumebacillus ginsengisoli sp. nov. is proposed. The type strain is Gsoil 1105(T) ( = KCTC 13942(T)  = DSM 18389(T)).

Antibacterial and antifungal activity of extracts and exudates of the Amazonian medicinal tree Himatanthus articulatus (Vahl) Woodson (common name: sucuba).

Himatanthus articulatus (Vahl) Woodson is a tree found in the northern Amazon savannahs (common name: sucuba) that is used in local Amerindian medicine. Leaf, bark and branch wood methanol extracts, sequentially obtained hexane, ethyl acetate and methanol extracts and latex were evaluated for antifungal and antibacterial activities against American Type Culture Collection (ATCC) and local clinical strains using the disc diffusion method. Methanol extracts and latex inhibited Candida albicans, leaf methanol extracts inhibited Staphylococcus aureus and Bacillus subtilis and bark methanol extracts inhibited B. subtilis. Active extracts inhibited the ATCC and clinical strains. Polar antifungal and antibacterial principles in latex and extracts are thought to be responsible for the inhibition.

Antibacterial and antifungal activity of extracts and exudates of the Amazonian medicinal tree Himatanthus articulatus (Vahl) Woodson (common name: sucuba)

Himatanthus articulatus (Vahl) Woodson is a tree found in the northern Amazon savannahs (common name: sucuba) that is used in local Amerindian medicine. Leaf, bark and branch wood methanol extracts, sequentially obtained hexane, ethyl acetate and methanol extracts and latex were evaluated for antifungal and antibacterial activities against American Type Culture Collection (ATCC) and local clinical strains using the disc diffusion method. Methanol extracts and latex inhibited Candida albicans, leaf methanol extracts inhibited Staphylococcus aureus and Bacillus subtilis and bark methanol extracts inhibited B. subtilis. Active extracts inhibited the ATCC and clinical strains. Polar antifungal and antibacterial principles in latex and extracts are thought to be responsible for the inhibition.

Paenibacillus pueri sp. nov., isolated from Pu'er tea.

Pu'er tea is a fermented drink made from the leaves of the tea plant, Camellia sinensis. Two novel bacteria, designated strains b09i-3(T) and b13i-1, were isolated during the process of fermentation of this tea. These isolates were Gram-positive, endospore-forming, motile rods that grew at 25-42 degrees C and pH 5.5-10.4. The DNA G+C content was 56.6-58.4 mol%, the predominant isoprenoid quinone was MK-7 and the predominant cellular fatty acid was anteiso-C(15 : 0) (49.0-50 % of the total). Phylogenetic analysis based on 16S rRNA gene sequences showed that strains b09i-3(T) and b13i-1 shared 99.9 % similarity and were affiliated with a cluster within the family Paenibacillaceae. Strains b09i-3(T) and b13i-1 were related most closely to Paenibacillus ginsengihumi DCY16(T) (97 % 16S rRNA gene sequence similarity). Levels of DNA-DNA relatedness between the two novel isolates and P. ginsengihumi DCY16(T) were below 56 %. The phylogenetic and phenotypic characteristics of these novel isolates allowed them to be distinguished clearly from recognized species of the genus Paenibacillus. Based on these data, strains b09i-3(T) and b13i-1 are considered to represent a novel species of the genus Paenibacillus, for which the name Paenibacillus pueri sp. nov. is proposed. The type species is b09i-3(T) (=KCTC 13223(T)=CECT 7360(T)).

Brevibacillus panacihumi sp. nov., a beta-glucosidase-producing bacterium.

Two Gram-positive-staining, endospore-forming, rod-shaped, motile bacteria, strains DCY35(T) and C17, were isolated from soil of a ginseng field in South Korea and were characterized in order to determine their taxonomic positions. 16S rRNA gene sequence analysis revealed that the two strains belonged to the family Paenibacillaceae; strain DCY35(T) showed highest levels of similarity to strain C17 (99.9 %), Brevibacillus invocatus LMG 18962(T) (98.9 %), B. centrosporus DSM 8445(T) (98.0 %), B. borstelensis DSM 6347(T) (97.6 %), B. formosus DSM 9885(T) (97.4 %), B. agri DSM 6348(T) (97.3 %), B. brevis DSM 30(T) (97.3 %) and B. levickii LMG 22481(T) (97.0 %). Chemotaxonomic analyses revealed that strains DCY35(T) and C17 possess menaquinone MK-7, common to members of the genus Brevibacillus, and that the predominant fatty acids were iso-C(15 : 0) (37.3 % of the total), anteiso-C(15 : 0) (32.9 %), iso-C(14 : 0) (11.8 %) and iso-C(16 : 0) (6.5 %). The results of physiological and biochemical tests clearly demonstrated that strains DCY35(T) and C17 represent a distinct species. Based on these data, the two strains are considered to represent a novel species of the genus Brevibacillus, for which the name Brevibacillus panacihumi sp. nov. is proposed. The type strain is DCY35(T) (=KCTC 13206(T) =JCM 15085(T)).

Paenibacillus camelliae sp. nov., isolated from fermented leaves of Camellia sinensis.

A novel bacterium, strain blls-2(T) was isolated from Pu'er tea. The isolate was Gram-positive, endospore-forming motile rod that grew at 15 approximately 42 degrees C and pH 6.0 approximately 10.2. The DNA G+C content was 48.3 mol%, the predominant isoprenoid quinone was MK-7, and the predominant cellular fatty acid was anteiso-C15:0 (54.2%) followed by C16:0 (15.5%) and iso-C16:0 (8.2%). The polar lipid pattern of blls-2(T) was characterized by the presence of diphosphatidylglycerol, phosphatidylethanolamine, and phosphatidylglycerol. Phy-logenetic analysis based on 16S rRNA gene sequence showed that the strain was affiliated within the Paenibacillaceae. The strain was most closely related to Paenibacillus granivorans A30(T), with a similarity of 97.1%. Based on the phylogenetic and phenotypic characteristics of strain blls-2(T), the isolate is thought to represent a novel taxon in the genus Paenibacillus. The name Paenibacillus camelliae sp. nov. is proposed for the fermented tea isolate; the type strain is blls-2(T) (= KCTC 13220(T)= CECT 7361(T)).

Effects of organic solvents on immobilized lipase in pectin microspheres.

Lipase from Brevibacillus agri 52 was found stable up to 90% diethylenglycol (DEG), glycerol (GLY), and 1,2 propanediol (1,2 PRO) at 37 degrees C for 1 h and the stability was reduced only approximately 20% after 12 h incubation, but in 40% dimethylsulfoxide (DMSO), lipase activity was stable only for 1 h. Inhibition of the biocatalysts with dimethylformamide (DMF) was detected at 20% solvent concentration. In water immiscible systems, the stability of lipase in n-hexane, n-tetradecane and n-heptane resembles the water activity, but in the presence of isobutanol, 1-hexanol, and butylbutirate, the stability was significantly reduced. Lipase 52 precipitates in the presence of 50% acetone or ethanol/water mixtures, but enzymatic activity was partially recovered by adding 20% GLY, DEG, 1,2 PRO, or DMSO to the reaction mixture. Furthermore, by increasing DEG in 70% DMF/DEG mixtures, the lipase activity was protected. Encapsulation of lipase in pectin gels cross-linked with calcium ions brings three to four times more enzymatic activity in 70% water miscible organic solvents compared to aqueous systems.

Paenibacillus ginsengihumi sp. nov., a bacterium isolated from soil in a ginseng field.

Strain DCY16T, a Gram-positive, spore-forming, rod-shaped, motile bacterium, was isolated from soil and characterized in order to determine its taxonomic position. 16S rRNA gene sequence analysis revealed that strain DCY16T belonged to the genus Paenibacillus; highest sequence similarities were with Paenibacillus validus JCM 9077T (94.4 %), P. chinjuensis WN9T (94.4 %), P. naphthalenovorans DSM 14203T (94.2 %), P. ehimensis KCTC 3748T (92.8 %) and P. elgii KCTC 10016BP(T) (92.4 %). Chemotaxonomic data revealed that strain DCY16T possessed menaquinone MK-7 and the predominant fatty acids were C15 : 0 anteiso, C17 : 0 anteiso, C16 : 0 and C16 : 0 iso. The DNA G+C content of strain DCY16T was 50.9 mol%. Results of physiological and biochemical tests clearly demonstrated that strain DCY16T represents a distinct Paenibacillus species. Based on these data, DCY16T (=KCTC 13141T =JCM 14928T) should be classified as the type strain of a novel species, for which the name Paenibacillus ginsengihumi sp. nov. is proposed.

Bovicin HC5 reduces thermal resistance of Alicyclobacillus acidoterrestris in acidic mango pulp.

AIMS: To test the effect of bovicin HC5 against vegetative cells and endospores of Alicyclobacillus acidoterrestris DSMZ 2498 in synthetic media and in acidic mango pulp. METHODS AND RESULTS: Alicyclobacillus acidoterrestris was grown in synthetic medium at 40 degrees C and pH 4.0. The effect on vegetative cells was assayed by adding bovicin HC5 to synthetic medium (40-160 AU ml(-1)) or to mango pulp (100 AU ml(-1)) at various pH values and determining the effect on growth (OD(600 nm)) and viable cell number, respectively. The effect of bovicin HC5 on spore germination and thermal sensitivity of A. acidoterrestris was tested in mango pulp (pH 4.0) containing 80 AU ml(-1) of bovicin HC5. Bovicin HC5 was bactericidal against vegetative cells of A. acidoterrestris at different pH values and showed sporicidal activity against endospores of this bacterium. When spores of A. acidoterrestris were heat treated in the presence of bovicin HC5, D-values decreased 77% to 95% compared to untreated controls at temperatures ranging from 80 to 95 degrees C. CONCLUSION: Bovicin HC5 was bactericidal and sporicidal against A. acidoterrestrsi DSMZ 2498. SIGNIFICANCE AND IMPACT OF THE STUDY: These results indicated that bovicin HC5 has potential to prevent spoilage of acidic fruit juices by thermocidophilic spore-forming bacteria.

Characterisation of Paenibacillus jamilae strains that produce exopolysaccharide during growth on and detoxification of olive mill wastewaters.

A total of 10 bacterial strains were isolated from a compost of corn treated with olive mill wastewaters (OMW) and selected by their capacity to synthesize exopolysaccharides (EPS). Morphological, physiological, biochemical and nutritional tests were used for a phenotypic study. A numerical analysis showed that all strains were 90% similar to each other. A DNA-DNA hybridization assay confirmed that all the strains belonged to Paenibacillus jamilae species. All the characterized strains were able to produce EPS growing on OMW batch cultures. The strain which was able to produce the highest EPS yield was chosen to perform an assay for testing its putative detoxifying activity, and it showed to reduce more than half the toxic capacity of the OMW. The results presented in this study, indicated the possible perspectives for using these bacterial strains to produce EPS and contribute to the bioremediation of the waste waters that are produced in the olive oil elaboration process.

Isolation and identification of an endophytic strain EJS-3 producing novel fibrinolytic enzymes.

An endophytic strain EJS-3, which produces a novel fibrinolytic enzyme, was screened from root tissue of Stemona japonica (Blume) Miq, a chinese traditional medicine. This strain was identified as Paenibacillus polymyxa (DQ120522) by morphological, physiological, and biochemical tests and 16S rRNA gene sequence analysis. Two serine-type fibrinolytic enzymes with a relative molecular weight about 118 and 49 kDa, respectively, which are larger than known fibrinolytic enzymes, were found by the SDS-fibrin zymogram or by fibrin-inhibitor zymography gels. No work on P. polymyxa-producing fibrinolytic enzymes has been reported.

Paenibacillus soli sp. nov., a xylanolytic bacterium isolated from soil.

Two novel polysaccharide-degrading bacteria (strains DCY03(T) and DCY04) were isolated from a soil sample of a ginseng field in the Republic of Korea and were identified as representing members of the genus Paenibacillus on the basis of phenotypic characteristics and phylogenetic inference based on 16S rRNA gene sequences. Cells of the two isolates were Gram-positive, spore-forming, non-motile, straight rods. Based on DNA-DNA relatedness data, the strains were considered to belong to the same species. The DNA G+C content ranged from 56.6 to 57.0 mol%. The predominant cellular fatty acid was anteiso-C(15 : 0) (63.8-62.8 %). Levels of 16S rRNA gene sequence similarity between the two novel isolates and the type strains of recognized Paenibacillus species were 91.4-96.5 %. Strains DCY03(T) and DCY04 could clearly be distinguished from phylogenetically closely related Paenibacillus species on the basis of DNA-DNA relatedness data and phenotypic characteristics. Therefore, on the basis of these data, the two isolates are considered to represent a novel species of the genus Paenibacillus, for which the name Paenibacillus soli sp. nov. is proposed. The type strain is DCY03(T) (=KCTC 13010(T)=LMG 23604(T)).

Brevibacillus ginsengisoli sp. nov., a denitrifying bacterium isolated from soil of a ginseng field.

A Gram-positive, rod-shaped, spore-forming bacterium, Gsoil 3088T, was isolated from soil from a ginseng field in Pocheon Province in South Korea and characterized in order to determine its taxonomic position. On the basis of 16S rRNA gene sequence similarity, strain Gsoil 3088T was shown to belong to the family Paenibacillaceae, being related to Brevibacillus centrosporus (96.6%), Brevibacillus borstelensis (96.3%), Brevibacillus parabrevis (96.1%), Brevibacillus formosus (96.1%), Brevibacillus brevis (96.1%) and Brevibacillus laterosporus (96.0%). The phylogenetic distances from other validly described species within the genus Brevibacillus were greater than 4.0% (i.e. there was less than 96.0% similarity). The G+C content of the genomic DNA was 52.1 mol%. Phenotypic and chemotaxonomic data (major menaquinone, MK-7; fatty acid profile, iso-C15:0, iso-C14:0 and anteiso-C15:0) supported the affiliation of strain Gsoil 3088T to the genus Brevibacillus. The results of physiological and biochemical tests allowed strain Gsoil 3088T to be distinguished genotypically and phenotypically from Brevibacillus species with validly published names. Strain Gsoil 3088T, therefore, represents a novel species of the genus Brevibacillus, for which the name Brevibacillus ginsengisoli sp. nov. is proposed. The type strain is Gsoil 3088T (=KCTC 13938T=LMG 23403T).

Production of a metal-binding exopolysaccharide by Paenibacillus jamilae using two-phase olive-mill waste as fermentation substrate.

The present study investigated the use of two-phase olive mill waste (TPOMW) as substrate for the production of exopolysaccharide (EPS) by the endospore-forming bacilli Paenibacillus jamilae. This microorganism was able to grow and produce EPS in aqueous extracts of TPOMW as a unique source of carbon. The effects of substrate concentration and the addition of inorganic nutrients were investigated. Maximal polymer yield in 100-ml batch-culture experiments (2 g l(-1)) was obtained in cultures prepared with an aqueous extract of 20% TPOMW (w/v). An inhibitory effect was observed on growth and EPS production when TPOMW concentration was increased. Nutrient supplementation (nitrate, phosphate, and other inorganic nutrients) did not increase yield. Finally, an adsorption experiment of Pb (II), Cd (II), Cu (II), Zn (II), Co (II), and Ni (II) by EPS is reported. Lead was preferentially complexed by the polymer, with a maximal uptake of 230 mg/g EPS.

Pectinolytic systems of two aerobic sporogenous bacterial strains with high activity on pectin.

Strains Paenibacillus sp. BP-23 and Bacillus sp. BP-7, previously isolated from soil from a rice field, secreted high levels of pectinase activity in media supplemented with pectin. Production of pectinases in strain Paenibacillus sp. BP-23 showed catabolite repression, while in Bacillus sp. BP-7 production of pectin degrading enzymes was not negatively affected by glucose. The two strains showed lyase activities as the predominant pectinases, while hydrolase activity was very low. Analysis of Paenibacillus sp. BP-23 in SDS-polyacrylamide gels and zymograms showed five pectinase activity bands. The strict requirement of Ca(2+) for lyase activity of the strain indicates that correspond to pectate lyases. For Bacillus sp. BP-7, zymograms showed four bands of different size. The strain showed a Ca(2+) requirement for lyase activity on pectate but not on pectin, indicating that the pectinolytic system of Bacillus sp. BP-7 is comprised of pectate lyases and pectin lyases. The results show differences in pectin degrading systems between the two aerobic sporogenous bacterial strains studied.

Mahella australiensis gen. nov., sp. nov., a moderately thermophilic anaerobic bacterium isolated from an Australian oil well.

A novel Gram-positive, anaerobic and moderately thermophilic bacterium, strain 50-1 BON(T), was isolated from an Australian terrestrial oil reservoir. Cells were spore-forming straight rods, motile by peritrichous flagella. The optimum growth conditions were 50 degrees C, pH 7.5 and 0.1 % NaCl. Strain 50-1 BON(T) fermented arabinose, cellobiose, fructose, galactose, glucose, mannose, sucrose, xylose and yeast extract. Glucose was fermented mainly into lactate, formate, hydrogen and CO(2). The major end product of pyruvate fermentation was acetate together with H(2) and CO(2). Thiosulfate, sulfate, elemental sulfur and nitrate were not used as terminal electron acceptors. The DNA G+C content was 55.5 mol%. The closest phylogenetic relative of strain 50-1 BON(T) was Thermoanaerobacterium thermosulfurigenes (16S rRNA gene sequence similarity of 85.7 %). As strain 50-1 BON(T) was physiologically and phylogenetically different from members of the order 'Thermoanaerobacteriales', it is proposed that strain 50-1 BON(T) (=DSM 15567(T)=CIP 107919(T)) be classified as the type strain of a novel species of a new genus, Mahella australiensis gen. nov., sp. nov.

Alicyclobacillus herbarius sp. nov., a novel bacterium containing omega-cycloheptane fatty acids, isolated from herbal tea.

A thermo-acidophilic gram-positive bacterium, strain CP-1T, which grows aerobically at 35-65 degrees C (optimum 55-60 degrees C) and at pH 3.5-6.0 (optimum pH 4.5-5.0), was isolated from a herbal tea made from the dried flowers of hibiscus. Phylogenetic analysis of the 16S rRNA gene sequences showed that this bacterium was clearly distinguishable from previously described species of the genera Alicyclobacillus and Sulfobacillus. Strain CP-1T had unique omega-cycloheptane fatty acids as the major membrane lipid component, a characteristic which is peculiar to Alicyclobacillus cycloheptanicus. However, phenotypic and chemotaxonomic characteristics of strain CP-1T were different from those of the type strain of A. cycloheptanicus. DNA-DNA hybridization between the type strains of Alicyclobacillus species and Sulfobacillus disulfidooxidans was <20%, indicating that strain CP-1T represents a distinct species. On the basis of these results, the name Alicyclobacillus herbarius is proposed for this organism. The type strain is strain CP-1T (= DSM 13609T = IAM 14883T = NRIC 0477T).