Paenibacillus nicotianae sp. nov., isolated from a tobacco sample

A Gram-stain positive, facultative anaerobic endospore-forming bacterium, designated strain YIM h-19^T, was isolated from a tobacco sample. Cells were observed to be motile rods by means of peritrichous flagella and colonies were observed to be convex, yellow, circular and showed catalase-positive and oxidase-negative reactions. Strain YIM h-19^T was able to grow at 4–45 °C, pH 6.0–8.0 and 0–3 % NaCl (w/v). The predominant respiratory quinone was identified as MK-7. Major fatty acids were identified as anteiso-C_15:0, anteiso-C_17:0 and C_16:0. The polar lipids were found to be phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol and two unidentified polar lipids. The genomic DNA G+C content was determined to be 54 mol%. 16S rRNA gene sequence analysis showed the strain YIM h-19^T was most closely related to Paenibacillus hordei RH-N24^T and Paenibacillus hunanensis FeL05^T with similarities of 98.30 and 94.64 % respectively. However, DNA–DNA hybridization data indicated that the isolate represented a novel genomic species with the genus Paenibacillus. All data from genotypic and phenotypic analyses support the conclusion that strain YIM h-19^T represents a novel species of the genus Paenibacillus, for which the name Paenibacillus nicotianae sp. nov. is proposed. The type strain is YIM h-19^T (=CGMCC1.12819^T = NRRL B-59112^T).     

Response of the population size and community structure of Paenibacillus spp. to different fertilization regimes in a long-term experiment of red soil

Background and aims

Paenibacillus spp. are widely considered to impact the fertility and health of soil. The aim of this study was to evaluate how different fertilization regimes affect the population size and community structure of Paenibacillus spp. over a long period of time in red soil.

Methods

Soil samples were collected from a long-term experiment and were then analyzed using real-time PCR and PCR-DGGE. The correlation analysis, PCA and RDA were used to explore the relationships among Paenibacillus spp. population, community structure and soil properties in different treatments.

Results

The pH was seriously decreased only by the application of chemical fertilizer. The largest population of Paenibacillus spp. was found in the soil treated with organic fertilizer application, while the richest diversity was observed in the soil treated only with the chemical fertilizer. The Paenibacillus spp., Paenibacillus alkaliterrae, Paenibacillus campinasensis, and Paenibacillus xylanilyticus were found in all treatments. Paenibacillus castaneae was found in the soil treated with NPK, and Paenibacillus pabuli was specifically observed in the lime-amended treatment. Paenibacillus taichungensis and Paenibacillus prosopidis were detected in the soil treated with only chemical fertilizer. Except for the ammonium and pH, all the tested soil fertility parameters (total C, total N, nitrate, available K and available P) could significantly affect both the Paenibacillus spp. population number and diversity. The soil pH was significantly correlated with Paenibacillus spp. diversity only.

Conclusions

Our results indicate that the different long-term fertilization regimes have varied impact on both the Paenibacillus spp. population size and the diversity of the community associated with the soil properties tested. These results can help to enrich the information on the response of beneficial soil microbes to different long-term fertilization regimes.     

Paenibacillus yonginensis sp. nov., a potential plant growth promoting bacterium isolated from humus soil of Yongin forest

Strain DCY84^T, a Gram-stain positive, rod-shaped, aerobic, spore-forming bacterium, motile by means of peritrichous flagella, was isolated from humus soil from Yongin forest in Gyeonggi province, South Korea. Strain DCY84^T shared the highest sequence similarity with Paenibacillus barengoltzii KACC 15270^T (96.86 %), followed by Paenibacillus timonensis KACC 11491^T (96.49 %) and Paenibacillus phoenicis NBRC 106274^T (95.77 %). Strain DCY84^T was found to able to grow best in TSA at temperature 30 °C, at pH 8 and at 0.5 % NaCl. MK-7 menaquinone was identified as the isoprenoid quinone. The major polar lipids were identified as phosphatidylethanolamine, an unidentified aminophospholipid, two unidentified aminolipids and an unidentified polar lipid. The peptidoglycan was found to contain the amino acids meso-diaminopimelic acid, alanine and d-glutamic acid. The major fatty acids of strain DCY84^T were identified as branched chain anteiso-C_15:0, saturated C_16:0 and branched chain anteiso-C_17:0. The cell wall sugars of strain DCY84^T were found to comprise of ribose, galactose and xylose. The major polyamine was identified as spermidine. The DNA G+C content was determined to be 62.6 mol%. After 6 days of incubation, strain DCY84^T produced 52.96 ± 1.85 and 72.83 ± 2.86 µg/ml l-indole-3-acetic acid, using media without l-tryptophan and supplemented with l-tryptophan, respectively. Strain DCY84^T was also found to be able to solubilize phosphate and produce siderophores. On the basis of the phenotypic characteristics, genotypic analysis and chemotaxonomic characteristics, strain DCY84^T is considered to represent a novel species of the genus Paenibacillus, for which the name Paenibacillus yonginensis sp. nov. is proposed. The type strain is DCY84^T (=KCTC 33428^T = JCM 19885^T).     

The Effects of Paenibacillus polymyxa E681 on Antifungal and Crack Remediation of Cement Paste

This study investigated the antifungal effects of cement paste containing Paenibacillus polymyxa E681 against Aspergillus niger, a deleterious fungus commonly found in cement buildings and structures. To test the antifungal effects, cement paste containing P. polymyxa E681 was neutralized by CO₂ gas, and the fungal growth inhibition was examined according to the clear zone around the cement specimen. In addition to the antifungal effects of the cement paste added with bacteria, calcium crystal precipitation of P. polymyxa E681 was examined by qualitative and quantitative analyses. The cement paste containing P. polymyxa E681 showed strong antifungal effects but fusA mutant (deficient in fusaricidin synthesis) showed no antifungal activity. Crack sealing of the cement paste treated with P. polymyxa E681 was captured by light microscope showed fungal growth inhibition and crack repairing in cement paste.     

Paenibacillus abyssi sp. nov., isolated from an abyssal sediment sample from the Indian Ocean

A Gram-positive, rod-shaped bacterium, designated strain SCSIO N0306^T, was isolated from an abyssal sediment sample collected from the Indian Ocean. The isolate was found to grow optimally at 0–2 % (w/v) NaCl, pH 7.0 and 30 °C. Comparative analysis of the 16S rRNA gene sequence showed that the isolate SCSIO N0306^T belongs phylogenetically to the genus Paenibacillus, and to be most closely related to P. algorifonticola XJ259^T (with 95.47 % sequence similarity), sharing less than 95.0 % sequence similarity with all other taxa of this genus. Chemotaxonomic analysis revealed MK-7 as the major isoprenoid quinone, the DNA G+C content was determined to be 45.5 mol%, and anteiso-C_15:0, C_16:0, and iso-C_15:0 were identified as the major fatty acids. On the basis of this polyphasic taxonomic data, isolate SCSIO N0306^T is considered to represent a novel species of the genus Paenibacillus, for which the name Paenibacillus abyssi sp. nov. is proposed. The type strain is SCSIO N0306^T (= DSM 26238^T = CGMCC 1.12987^T).     

Inactivation of the phosphoglucomutase gene pgm in Paenibacillus polymyxa leads to overproduction of fusaricidin

Fusaricidin, a lipodepsipeptide isolated from Paenibacillus polymyxa, has high antimicrobial activity against fungi and Gram-positive bacteria. Through mutagenesis, we obtained two mutant strains, N1U7 and N17U7, which produce 6.2- to 7.9-fold more fusaricidin than their parent strain. Causal mutations were identified by whole-genome sequencing, and the two strains each contained at least eleven point mutations, including four common mutations. A mutation in the PPE04441 gene (pgm), encoding an α-phosphoglucomutase, was found to be an important factor in fusaricidin overproduction by complementation experiments. Null mutation of pgm in the parental strain increased fusaricidin production by 5.2-fold. Increased growth and cell viability in stationary phase, reduced exopolysaccharide production, and increased fusA expression were observed in the pgm mutant strains, which might be related to fusaricidin overproduction. This is the first report revealing that PGM deficiency leads to an overproduction of fusaricidin.     

The C-terminal region of xylanase domain in Xyn11A from Paenibacillus curdlanolyticus B-6 plays an important role in structural stability

Paenibacillus curdlanolyticus B-6 produces an extracellular multienzyme complex containing a major xylanase subunit, designated Xyn11A, which includes two functional domains belonging to glycosyl hydrolase family-11 (GH11) and carbohydrate binding module family-36 (CBM36) and possesses a glycine and asparagine-rich linker (linker). To clarify the roles of each functional domain, recombinant proteins XynXL and XynX (CBM36 deleted and CBM36 and linker deleted, respectively) were constructed. Their xylanase activities were similar toward soluble xylan, whereas XynXL showed decreased hydrolysis activity toward insoluble xylan while XynX had no xylanase activity. To determine the significance of the linker and its neighbor region, XynX was subjected to secondary structural alignments using circular dichroism (CD) spectroscopy and three-dimensional (3D) structural analysis. A seven amino acid (NTITIGG) neighbor linker sequence was highly conserved among GH11 xylanases of Paenibacillus species. Although XynX exhibited a typical GH11 xylanase structure, conformational gaps were observed in the β6- and β12-sheets and in CD spectra. Flipping of the Arg163 side chains in the subsite was also observed upon analysis of superimposed models. Docking analysis using xylohexaose indicated that flipping of the Arg163 side chains markedly affected substrate binding in the subsite. To identify the amino acids related to stabilizing the substrate binding site, XynX with an extended C-terminal region was designed. At least seven amino acids were necessary to recover substrate binding and xylanase activity. These results indicated that the seven amino acid neighbor Xyn11A linker plays an important role in the activity and conformational stability of the xylanase domain.     

1H, 13C and 15N backbone and side-chain resonance assignments of a family 36 carbohydrate binding module of xylanase from Paenibacillus campinasensis

Paenibacillus campinasensis BL11 isolated from black liquor secretes multiple glycoside hydrolases (GHs) against all kinds of polysaccharides. GH consists of a catalytic module and non-catalytic carbohydrate-binding modules (CBMs), in which CBMs append to the catalytic module, mediating specific interactions with insoluble carbohydrates to promote the hydrolysis efficiency of the cognate enzyme. Endo-β-1,4-xylanase (XylX) is one of the GHs reveals high enzymatic activity in a wide range of pH and thermal endurance, suitable for bioconversion and bio-refinement applications. In this work, we report the resonance assignments of a family 36 CBM (characterized as CBM36) derived from XylX. Our investigations will facilitate molecular structure determination and molecular dynamics analysis of CBMs.     

Phylogeny of 16S rRNA and nifH genes and regulation of nitrogenase activity by oxygen and ammonium in the genus Paenibacillus

All Paenibacillus 16S rDNA sequences, except for that of Paenibacillus massiliensis T7, formed a coherent cluster, distinct from gram-positive nitrogen-fixing Clostridium pasteurianum and Heliobacterium chlorum. All Paenibacillus NifH sequences formed two main clusters. Cluster I encompassing the NifH sequences from most of members of Paenibacillus spp., such as Paenibacillus azotofixans NifH1 and NifH2, Paenibacillus polymyxa and Paenibacillus macerans. Cluster II including only P. azotofixans NifH3. Curiously, three copies of nifH genes of Paenibacillus sabine T27 clustered within P. azotofixans cluster I (NifH1 and NifH2). The effect of O₂ and ammonium on nitrogenase activity was studied with 14 different nitrogenfixing Paenibacillus strains. The optimal oxygen concentration level for all Paenibacillus strains is in the 0 to 0.05% range, similar to that for Klebsiella pneumoniae. In all Paenibacillus strains, the highest nitrogenase activity is obtained in the condition of 0?C0.1 mM NH₄Cl and the increase of NH₄Cl from 0.1 to 5 mM caused a rapid inhibition of nitrogenase activity. However, the inhibition was reversible in the presence of 200 mM NH₄Cl in some Paenibacillus strains. It is the first time to use almost all of the recognized nitrogen-fixing Paenibacilus spp. to investigate the phylogeny of 16S rRNA and nifH genes. The data that the inhibition of O₂ and ammonium on nitrogenase acitivity will provide a base for studying the molecular regulatory mechanism of nitrogen fixation in the genus Paenibacillus.     

Isolation and identification of Paenibacillus sp. FM-6, involved in the biotransformation of albendazole

A strain, designated as FM-6, was isolated from fish. Based on the results of phenotypic, physiological characteristics, genotypic and phylogenetic analysis, strain FM-6 was finally identified as Paenibacillus sp. When albendazole was provided as the sole carbon source, strain FM-6 could grow and transform albendazole. About 82.7 % albendazole (50 mg/L) was transformed by strain FM-6 after 5 days incubation at 30 °C, 160 rpm. With HPLC–MS method, the transforming product of albendazole was researched. Based on the molecular weight and the retention time, product was identified as albendazole sulfoxide and the transforming pathway of albendazole by strain FM-6 was proposed finally. The optimum temperature and pH for the bacterium growth and albendazole transformation by strain FM-6 were both 30 °C and 7.0. Moreover, the optimum concentration of albendazole for the bacterium growth was 50 mg/L. Coupled with practical production, 50 mg/L was the optimum concentration of albendazole transformation for strain FM-6. This study highlights an important potential use of strain FM-6 for producing albendazole sulfoxide.     

<Emphasis Type="Italic">Paenibacillus oryzisoli</Emphasis> sp. nov., isolated from the rhizosphere of rice

A novel bacterium, strain 1ZS3-15^T, was isolated from rhizosphere of rice. Its taxonomic position was investigated using a polyphasic approach. The novel strain was observed to be Gram-stain positive, spore-forming, aerobic, motile and rod-shaped. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain 1ZS3-15^T was recovered within the genus Paenibacillus. It is closely related to Paenibacillus pectinilyticus KCTC 13222^T (97.9 % similarity), Paenibacillus frigoriresistens CCTCC AB 2011150^T (96.8 %), Paenibacillus alginolyticus JCM 9068^T (96.4 %) and Paenibacillus chondroitinus DSM 5051^T (95.5 %). The fatty acid profile of strain 1ZS3-15^T, which showed a predominance of anteiso-C_15:0 and iso-C_16:0, supported the allocation of the strain into the genus Paenibacillus. The predominant menaquinone was found to be MK-7. The polar lipids profile of strain 1ZS3-15^T was found to consist of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, one unidentified lipid and two unidentified aminophospholipids. The cell wall peptidoglycan contains meso-diaminopimelic acid. Based on draft genome sequences, the DNA–DNA relatedness between strain 1ZS3-15^T and the closely related species P. pectinilyticus KCTC 13222^T are 24.2 ± 1.0 %, and the Average Nucleotide Identity values between the strains are 78.9 ± 0.1 %, which demonstrated that this isolate represents a new species in the genus Paenibacillus. The DNA G+C content was determined to be 45.3 mol%, which is within the range reported for Paenibacillus species. Characterisation by genotypic, chemotaxonomic and phenotypic analysis indicated that strain 1ZS3-15^T represents a novel species of the genus Paenibacillus, for which the name Paenibacillus oryzisoli sp. nov. is proposed. The type strain is 1ZS3-15^T (= ACCC 19783^T = JCM 30487^T).     

Paenibacillus beijingensis sp. nov., a nitrogen-fixing species isolated from wheat rhizosphere soil

A novel nitrogen-fixing bacterium, BJ-18^T, was isolated from wheat rhizosphere soil. Strain BJ-18^T was observed to be Gram-positive, facultatively anaerobic, motile and rod-shaped (0.4–0.9 μm × 2.0–2.9 μm). Phylogenetic analysis based on a partial nifH gene sequence and an assay for nitrogenase activity showed its nitrogen-fixing capacity. Phylogenetic analysis based on full 16S rRNA gene sequences suggested that strain BJ-18^T is a member of the genus Paenibacillus. High similarity of 16S rRNA gene sequence was found between BJ-18^T and Paenibacillus peoriae DSM 8320^T (99.05 %), Paenibacillus jamilae DSM 13815^T (98.86 %), Paenibacillus brasiliensis DSM 13188^T (98.55 %), Paenibacillus polymyxa DSM 36^T (98.74 %), Paenibacillus terrae DSM 15891^T (97.99 %) and Paenibacillus kribbensis JCM 11465^T (97.92 %), whereas the similarity was below 96.0 % between BJ-18^T and the other Paenibacillus species. DNA–DNA relatedness between strain BJ-18^T and P. peoriae DSM 8320^T, P. jamilae DSM 13815^T, P. brasiliensis DSM 13188^T, P. polymyxa DSM 36^T, P. kribbensis JCM 11465^T and P. terrae DSM 15891^T was determined to be 43.6 ± 2.7, 34.2 ± 5.3, 47.9 ± 6.6, 36.8 ± 3.5, 27.4 ± 4.3 and 23.6 ± 4.1 % respectively. The DNA G+C content of BJ-18^T was determined to be 45.8 mol %. The major fatty acid was identified as anteiso-C_15:0 (67.1 %). The polar lipids present in strain BJ-18^T were identified as diphosphatidylglycerol, phosphatidyl methylethanolamine, phosphatidylethanolamine and phosphatidylglycerol. The phenotypic and genotypic characteristics, and DNA–DNA relatedness data, suggest that BJ-18^T represents a novel species of the genus Paenibacillus, for which the name Paenibacillus beijingensis sp. nov. (Type strain BJ-18^T=DSM25425^T=CGMCC 1.12045^T) is proposed.     

Particulate matter and bacteria characteristics of the Middle East Dust (MED) storms over Ahvaz,Iran

The Middle East Dust storms have greatly affected the south and west parts of Iran during the last decade. The main purpose of this study was to examine and compare culturable airborne bacteria concentration in particulate matter (PM) during normal, semi-dust, and dust event days in different places and seasons in Ahvaz from November 2011 to May 2012. Sampling was performed every 6 days and on dust event days at different sampling stations. The overall mean concentrations of PM₁₀, PM_2.5, and PM₁ for the entire study period were 598.92, 114.8, and 34.5 μg/m³, respectively. The PM concentrations during the dust event days were much higher than normal and semi-dust event days. The highest mean PM concentrations were observed in March 2011. The low PM_2.5/PM₁₀ ratios indicate that these PM are mostly originating from natural sources such as dust storms. The overall mean concentration of total bacteria during the study period was 620.6 CFU/m³. The greatest bacterial concentrations were observed during dust event days and at areas with high traffic and more human activities compared with normal days and greener areas. The percentage of gram-positive bacteria was significantly higher than that during the study period (89 vs 11 %). During this study, 26 genera of culturable bacteria were identified from all the sampling stations. The most dominant genera in all sampling stations were Streptomyces, Bacillus, Kocuria, Corynebacterium, and Paenibacillus. The results also showed that there were positive correlations between PM and bacterial concentrations during the study period (p < 0.05).     

Proteomic response of Rhizoctonia solani GD118 suppressed by Paenibacillus kribbensis PS04

Rice sheath blight, caused by Rhizoctonia solani, is considered a worldwide destructive rice disease and leads to considerable yield losses. A bio-control agent, Paenibacillus kribbensis PS04, was screened to resist against the pathogen. The inhibitory effects were investigated (>80 %) by the growth of the hyphae. Microscopic observation of the hypha structure manifested that the morphology of the pathogenic mycelium was strongly affected by P. kribbensis PS04. To explore essentially inhibitory mechanisms, proteomic approach was adopted to identify differentially expressed proteins from R. solani GD118 in response to P. kribbensis PS04 using two-dimensional gel electrophoresis. Protein profiling was used to identify 13 differential proteins: 10 proteins were found to be down-regulated while 3 proteins were up-regulated. These proteins were involved in material and energy metabolism, antioxidant activity, protein folding and degradation, and cytoskeleton regulation. Among them, material and energy metabolism was differentially regulated by P. kribbensis PS04. Protein expression was separately inhibited by the bio-control agent in oxidation resistance, protein folding and degradation, and cytoskeleton regulation. Proteome changes of the mycelium assist in understanding how the pathogen was directly suppressed by P. kribbensis PS04.     

Aerobic endospore-forming bacteria isolated from Antarctic soils as producers of bioactive compounds of industrial interest

Spore-forming bacteria are known to produce various enzymes and bioproducts valuable to different industries and to bear the harsh conditions found in the Antarctic environment. However, aerobic or facultative spore-forming bacterial communities found in maritime Antarctic soils yet remain poorly studied. In this study, 80 spore-forming and cold-adapted bacterial strains were isolated from nine different soil samples of King George Island, in maritime Antarctica, and further clustered into amplified ribosomal DNA restriction analysis groups within each soil. Representative strains were then identified as belonging to Bacillus, Rummeliibacillus, Paenibacillus and Sporosarcina by 16S rRNA gene sequencing. The ability to produce extracellular enzymes, antimicrobial substances and biosurfactants was determined in all isolates. The enzymatic activities most frequently found among the isolates were as follows: esterase (45 %), caseinase (30 %), amylase (16.2 %) and gelatinase (15 %). Biosurfactant production was detected in 25 % of the isolates. The growth inhibition of methicillin-resistant Staphylococcus aureus was observed in 13.7 % of the strains tested, but only two strains inhibited the growth of Candida albicans. The isolated spore-forming bacterial species were also compared with the characteristics of the different Antarctic soils sampled based on their physicochemical properties, showing that pH, C and P were the main factors correlated with the distribution of this group of bacteria in the Antarctic soils studied. These Antarctic endospore-forming bacterial strains may have a potential for industrial processes occurring at low temperatures.     

Purification and Characterization of Exo-Inulinase from <Emphasis Type="Italic">Paenibacillus</Emphasis> sp. d9 Strain

This study intended to purify and characterise exo-inulinase of diesel-degrading Paenibacillus sp. D9. The whole genome sequencing of Paenibacillus sp. D9 revealed to possess the sacC gene that is encoded as exo-inulinase/levanase. This isolate was capable of producing a maximum of 50.9 IU/mL of exo-inulinase activity within 3 days at 30?°C, 200 rpm and pH of 7.0 on minimal salt medium agar supplemented with 1% (w/v) inulin. An exo-inulinase of 58.5 kDa was purified using ammonium sulphate precipitation, HiTrap QFF column and MMC column chromatographies with a specific activity of 4333 IU/mg, 7.1% recovery and a 4.3-fold increase in purity. The purified D9 exo-inulinase had temperature and pH optimum at 40?°C and pH 4.0, respectively, with the Michaelis constant of 5.5 mM and a maximal velocity of 476.2 IU/mg, respectively. Catalytic constant, k _cat was calculated to be 42.6 s^?1 with a catalytic efficiency (k _cat /K _m ) of 7.6 s^?1 mM^?1. The presence of Ca²⁺ enhanced the activity of D9 exo-inulinase while Hg²⁺ completely inhibited the activity, other compounds such as Fe³⁺ and Cu²⁺ had an inhibitory effect. The results of amino acid alignment and the complete degradation of inulin into fructose by the purified enzyme confirmed that inulinase from Paenibacillus sp. D9 is an exo-form. The phylogenetic tree based on the protein sequences indicates that bacterial exo-inulinases possess a common ancestry.     

Cloning,expression, and characterization of a thermostable glucose-6-phosphate dehydrogenase from <Emphasis Type="Italic">Thermoanaerobacter tengcongensis</Emphasis>

Glucose-6-phosphate dehydrogenases (G6PDs) are important enzymes widely used in bioassay and biocatalysis. In this study, we reported the cloning, expression, and enzymatic characterization of G6PDs from the thermophilic bacterium Thermoanaerobacter tengcongensis MB4 (TtG6PD). SDS-PAGE showed that purified recombinant enzyme had an apparent subunit molecular weight of 60 kDa. Kinetics assay indicated that TtG6PD preferred NADP⁺ (k _cat/K _m = 2618 mM^?1 s^?1, k _cat = 249 s^?1, K _m = 0.10 ± 0.01 mM) as cofactor, although NAD⁺ (k _cat/K _m = 138 mM^?1 s^?1, k _cat = 604 s^?1, K _m = 4.37 ± 0.56 mM) could also be accepted. The K _m values of glucose-6-phosphate were 0.27 ± 0.07 mM and 5.08 ± 0.68 mM with NADP⁺ and NAD⁺ as cofactors, respectively. The enzyme displayed its optimum activity at pH 6.8–9.0 for NADP⁺ and at pH 7.0–8.6 for NAD⁺ while the optimal temperature was 80 °C for NADP⁺ and 70 °C for NAD⁺. This was the first observation that the NADP⁺-linked optimal temperature of a dual coenzyme-specific G6PD was higher than the NAD⁺-linked and growth (75 °C) optimal temperature, which suggested G6PD might contribute to the thermal resistance of a bacterium. The potential of TtG6PD to measure the activity of another thermophilic enzyme was demonstrated by the coupled assays for a thermophilic glucokinase.     

Characterization and expression of glucosamine-6-phosphate synthase from Saccharomyces cerevisiae in Pichia pastoris

Glucosamine-6-phosphate (GlcN-6-P) synthase from Saccharomyces cerevisiae was expressed in Pichia pastoris SMD1168 GIVING maximum activity of 96 U ml^?1 for the enzyme in the culture medium. By SDS-PAGE, the enzyme, a glycosylated protein, had an apparent molecular mass of 90 kDa. The enzyme was purified by gel exclusion chromatography to near homogeneity, with a 90 % yield and its properties were characterized. Optimal activities were at pH 5.5 and 55 °C, respectively, at which the highest specific activity was 6.8 U mg protein ^?1. The enzyme was stable from pH 4.5 to 5.5 and from 45 to 60 °C. The K_m and V_max of the GlcN-6-P synthase towards d-fructose 6-phosphate were 2.8 mM and 6.9 μmol min^?1 mg^?1, respectively.     

Paenibacillus profundus sp. nov., a deep sediment bacterium that produces isocoumarin and peptide antibiotics

A novel bacterial strain Sl 79^T was isolated from a deep surface sediment sample obtained from the Sea of Japan and investigated by phenotypic and molecular methods. The bacterium Sl 79^T was Gram-positive, facultatively anaerobic, spore-forming, motile and able to form two different types of colonies. It contained the major menaquinone MK-7 and anteiso-C_15:0 followed by iso-C_15:0 as predominant fatty acids. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain Sl 79^T belonged to the genus Paenibacillus where it clustered to Paenibacillus apiarius NRRL NRS-1438^T with a sequence similarity of 97.7 % and sharing sequence similarities below than 96.7 % to other validly named Paenibacillus species. Strain Sl 79^T was found to possess a remarkable inhibitory activity against indicatory microorganisms. On the basis of combined spectral analyses, strain Paenibacillus sp. Sl 79^T was established to produce isocoumarin and novel peptide antibiotics. On the basis of DNA–DNA relatedness, phenotypic and phylogenetic data obtained, it was concluded that strain Sl 79^T represents a novel species, Paenibacillus profundus sp. nov. with the type strain Sl 79^T = KMM 9420^T = NRIC 0885^T.