Cellulosimicrobium Funkei Research Articles

Multi-metal resistance and antibiotic susceptibility of biofilm forming bacteria isolated from Kuzhikandam Creek in Kochi, southwest part of India

The purpose of this work was to characterize and identify the bacteria isolated from highly polluted locations that could potentially be able to withstand extremely toxic heavy metals. The study area selected for bacterial isolation from sediment samples was Kuzhikandam Creek, a tributary of the Periyar River and one of the world’s most hazardous hotspots, located in Kochi’s Eloor industrial region. Heavy metal analysis of chromium, copper, and lead in sediment samples was performed, and the results showed that the concentrations were greater than permissible limits. Several metal-resistant bacteria were isolated from sediments, which, upon further screening in solid media at different concentrations of chromium, copper, and lead, found three highly resistant species (S1B1, S2B2, and S3B3), one from each site. The phenotypic and biochemical characterization of these bacteria was examined using standard procedures. The ability of these species to generate biofilm was examined using methods like the crystal violet assay (qualitative assessment) and also using the scanning electron microscope. The antibiotic susceptibility of these species was tested with six different antibiotics, which are used in various disease treatments. These isolates, sequenced using the 16S rRNA Sanger dideoxy method, have been identified as Staphylococcus arlettae, Bacillus paramycoides, and Cellulosimicrobium funkei.

Identification of pigmented extremophilic bacteria from mangrove soil with antibiofilm activity on food pathogens

Mangrove ecosystems and associated microorganisms are always a source of curiosity for researchers. Pigment producing bacteria were isolated from the mangrove soil in Kadamakkudi, Cochin, Kerala. The bacteria were biochemically identified and by 16 S rRNA gene sequence. The pigments extracted had been tested for antibiofilm activity against food pathogens Pseudomonas aeruginosa (NCIM 2863), Klebsiella pneumoniae (NCIM 5215), and Escherichia coli (NCIM 2343). Antibiofilm activity was further confirmed by fluorescent and scanning electron microscopy. Six yellow-orange pigmented bacteria (KDR2, KDR3, KDR7, KDR8, KDR14 and KDS1) were isolated. KDR2 was identified as Cellulosimicrobium funkei, KDR7 and KDS1 as Cytobacillus depressus, KDR8 as Bacillus aquimaris, and KDR3 and KDR14 as Halobacillus sp. All of these organisms are known to be extremophiles. The UV-Visible absorption spectrum of all the pigments ranged from 400 nm to 550 nm with different absorbance maxima. All the pigments showed antibiofilm activity against the food pathogens tested.

Safety evaluation of a second extension of use of the food enzyme α-amylase from the non-genetically modified Cellulosimicrobium funkei strain AE-AMT.

The food enzyme α-amylase (4-α-d-glucan glucanohydrolase i.e. EC 3.2.1.1) is produced with the non-genetically modified Cellulosimicrobium funkei strain AE-AMT by Amano Enzyme Inc. A safety evaluation of this food enzyme was made previously, in which EFSA concluded that the food enzyme did not give rise to safety concerns when used in seven food manufacturing processes. Subsequently, the applicant has requested to extend its use to include three additional processes. In this assessment, EFSA updated the safety evaluation of this food enzyme when used in a total of ten food manufacturing processes. As the food enzyme-total organic solids (TOS) are removed from the final foods in one food manufacturing process, the dietary exposure to the food enzyme-TOS was estimated only for the remaining nine processes. The dietary exposure was calculated to be up to 0.049 mg TOS/kg body weight (bw) per day in European populations. When combined with the no observed adverse effect level previously reported (230 mg TOS/kg bw per day, the highest dose tested), the Panel derived a margin of exposure of at least 4694. Based on the data provided for the previous evaluation and the revised margin of exposure in the present evaluation, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use.

Updated safety evaluation of the food enzyme α-amylase from the non-genetically modified Cellulosimicrobium funkei strain AE-AMT.

The food enzyme α-amylase (4-α-d-glucan glucanohydrolase; EC 3.2.1.1) is produced with the non-genetically modified Cellulosimicrobium funkei strain AE-AMT by Amano Enzyme Inc. In a previous opinion, a safety evaluation of this food enzyme was completed, in which EFSA concluded that this food enzyme did not give rise to safety concerns when used in starch processing for maltodextrin production. The applicant has now provided new data to extend the use of this food enzyme to six additional food manufacturing processes: baking processes, cereal-based processes, plant processing for the production of dairy analogues, processing of tea, herbal and fruit infusions, brewing processes and the production of non-wine vinegar. For its use in a total of seven food manufacturing processes, the dietary exposure to the food enzyme-total organic solids (TOS) was estimated to be up to 0.012 mg TOS/kg body weight (bw) per day in European populations. Using the toxicological data provided in the previous opinion, with a NOAEL of 230 mg TOS/kg bw per day (the highest dose tested), the Panel derived a margin of exposure of at least 19,167. Based on the revised exposure calculation and the outcome of the previous evaluation, the Panel concluded that this food enzyme does not give rise to safety concerns under the revised intended conditions of use.

Production and application of purified mutanase from novel Cellulosimicrobium funkei SNG1 in the in vitro biofilm degradation.

Mutanase (α-1,3-glucanase) is an inducible extracellular enzyme with potential medical applications in dentistry. A novel Cellulosimicrobium funkei strain SNG1 producing mutanase enzyme using α-1,3-glucans was isolated, and the enzyme was optimized for increased productivity using the one-factor-at-a-time approach. Maximum growth and enzyme-specific activity (2.12 ± 0.4U/mg) were attained in a production medium with pH 7.0 and 1% α-1,3-glucans as carbon source, incubated at 37°C for 30h. The result showed a five-fold increase in activity compared to unoptimized conditions (0.40U/mg). The enzyme was purified by gel-filtration chromatography, and recovered with a yield of 29.03% and a specific activity increase of 10.9-fold. The molecular mass of the monomeric enzyme is 137kDa. The pH and temperature optima are 6.0 and 45°C with Km of 1.28 ± 0.11mg for α-1,3-glucans. The enzyme activity was stimulated by adding Co2+ , Ca2+ , Cu2+ , and was entirely inhibited by Hg2+ . On 2-h incubation, the purified enzyme effectively degraded in vitro film with an 82.68% degradation rate and a saccharification yield of 30%.

Safety evaluation of the food enzyme endo-1,3(4)-β-glucanase from the non-genetically modified Cellulosimicrobium funkei strain AE-TN.

The food enzyme endo-1,3(4)-β-glucanase (3-(1-3;1-4)-β-d-glucan 3(4)-glucanohydrolase; EC 3.2.1.6) is produced with the non-genetically modified Cellulosimicrobium funkei strain AE-TN by Amano Enzyme Inc. The food enzyme was shown to contain viable cells of the production strain, which belongs to a species that has been implicated in opportunistic infections in humans. The food enzyme is intended to be used in baking processes and yeast processing. Dietary exposure to the food enzyme total organic solids (TOS) was estimated to be up to 1.75mg TOS/kg body weight (bw) per day in European populations. Genotoxicity tests did not raise a safety concern. The systemic toxicity was assessed by means of a repeated dose 90-day oral toxicity study in rats. The Panel identified a no observed adverse effect level of 1,788mg TOS/kg bw per day, the highest dose tested, which, when compared with the estimated dietary exposure, resulted in a margin of exposure of at least 1,022. A search for the similarity of the amino acid sequence of the food enzyme to known allergens was made and no match was found. The Panel considered that, under the intended conditions of use, the risk of allergic reactions by dietary exposure cannot be excluded, but the likelihood for this to occur is low. However, due to the presence of viable cells of the production strain in the food enzyme, the Panel concluded that the food enzyme cannot be considered safe.

Extremotolerant Gelatinase Enzyme Production by UCM4 Bacterial Strain Isolated from the Rhizospheric Soil of Rhizophora mangle

Gelatinases are important metalloproteases which specifically act on gelatin. Gelatinase hydrolyze gelatin into polypeptides, peptides and amino acids which can cross the cell membrane to get utilized by the organisms. Gelatinase and collagenase are not only used in chemical and medical field but also in food and basic biological sciences. Since gelatinase has potential applications and high demands, the search for new isolates producing gelatinase with extremotolerant property is significant. In the present study we focus on potential extremotolerant gelatinase production from Cellulosimicrobium funkei strain UCM4 isolated from the rhizospheric soil of Rhizophora mangle from coastal regions of Dakshina Kannada, Karnataka, India. The isolate was tested for extremotolerant property with potential gelatinase production in extreme physiological conditions such as pH, salinity and temperature. The isolate showed 56,500 μg/ml of gelatinase production at its optimum growth conditions. The gelatinase production was increased with increase in pH from 7 to 11 which was between 56,500 μg/ml to 58,888.3 μg/ml. Gelatinase production was observed at temperature ranges from 30°C to 40°C which was between 57,777.2 μg/ml to 55,555 μg/ml, and salinity ranges from 0% to 5% NaCl (w/v) which was between 56,500 μg/ml to 49,999.5 μg/ml. The study revealed that the Cellulosimicrobium funkei strain UCM4 has ability to produce extremotolerant gelatinase and hence UCM4 has its potentiality for industrial scale production of gelatinase enzyme and the results will stand as a base line data for the production and application of gelatinase in future.

ANTAGONISTIC ACTIVITY OF MARINE BACTERIA FROM KARIMUN ISLAND, INDONESIA

Antimicrobial resistance (AMR) is becoming a major global crisis in the public healthcare system. One of the issues is the misuse of antimicrobials that will accelerate the AMR phenomenon. Discovering new antimicrobial compounds from various sources and places is an alternative way to resolve this problem. Marine bacteria were known as a new promising source for bioactive compounds. The marine bacteria were isolated from marine sediment using 1/5 NBRC 802 agar and seawater agar supplemented with 10mM NH4Cl. All isolates were subjected to antagonistic activity against Escherichia coli, Bacillus subtilis, and Staphylococcus aureus using the disk diffusion method. The selected isolates were then identified based on the 16S rRNA gene sequence. A total of 65 bacterial isolates have been successfully isolated from the seawater and marine sediment from Karimun Island. Of the 65 isolates, 12 isolates showed activity against tested bacteria; seven isolates against B. subtilis, two isolates against S. aureus, one isolate against E. coli, one isolate against B. subtilis and S. aureus, and one isolate against S. aureus and E. coli. The 16S rDNA sequences showed that the selected isolates belong to Cellulosimicrobium funkei, Gordonia sp., Kocuria salina, Micrococcus aloeverae, Micromonospora aurantiaca, Mumia sp., Nocardioides sp., and Pseudoalteromonas shioyasakiensis. Most of the isolates with antibacterial activity were identified as Actinobacteria and one isolate from the Gammaproteobacteria. Isolate KRSd2(2) shared 97,79% identity with Gordonia bronchialis. Further, a taxonomical study of the isolate compared with known species and chemical analysis of bioactive compounds are needed.

Investigating the diversity of bacterial endophytes in maize and their plant growth-promoting attributes.

Maize is a widely known crop in cereals for its importance as staple food, and the endophytic bacteria which dwell within the maize tissues may have impact on the yield and quality of crop. In this study, endophytic bacteria associated with maize were characterized based on their plant growth promoting traits and identified at molecular level to provide valuable information for developing a microbial consortium to enhance the productivity of crop. The bacterial strains having multi-trait plant growth promoting attributes were studied quantitatively, and highest phosphate solubilization was shown by the isolate KL3E1 (573µg/mL), while K solubilization has reported maximum of 39mg/L by the isolate PdS3E1, IAA production was found maximum by the isolate LL3E1 (165μg/mL), and maximum siderophore production (93%) was shown by the isolate VaR3E1 and exopolysaccharide production was found highest by LS3E3 (65mg/L). The efficient isolates identified by 16S rRNA gene sequencing were found as Gordonia hongkongensis, Microbacterium hydrothermale, Kosakonia radicincitans, Kosakonia cowanii, Priestia megaterium, Priestia aryabhattai, Klebsiella pneumoniae, Cellulosimicrobium funkei, Bacillus licheniformis, Pantoea dispersa, Pseudomonas aeruginosa, and Methylorubrum populi. The results showed that these multi-trait plant growth promoting endophytic bacterial isolates could be used as bio inoculants for sustainable improvement of maize crop productivity.

Two liquid phase partitioning bioreactor system for toxicant free water production from phthalates contaminated aqueous medium

Biodegradation of DMP (dimethyl phthalate) and DEP (diethyl phthalate) is a global environmental concern due to their endocrine disrupting nature. In the present study, biodegradation of DEP as the single substrate and a mixture of DMP and DEP as dual substrates were examined in a two-phase partitioning bioreactor (TPPB) using Cellulosimicrobium funkei. The TPPB system was run under batch and fed-batch modes of operation at different initial concentrations of DEP and mixture of DMP and DEP. Under the batch mode of operation, 93% degradation was achieved by C. funkei within 60 h with 38.75 mgL−1h−1 degradation rate. In the fed-batch system, complete degradation was observed up to 3500 mg/L total initial concentration of the phthalates (1500 mg/L DEP and 2000 mg/L DMP) within 24h. Phytotoxicity assessment of the treated water by seed germination and brine shrimp lethality assays revealed a germination index value of 86.17 and 13.33% brine shrimp mortality. Overall, this study revealed a very good potential of the TPPB system for detoxification of endocrine disrupting chemicals in the environment.

Safety evaluation of the food enzyme α-amylase from Cellulosimicrobium funkei strain AE-AMT.

The food enzyme α‐amylase (4‐α‐d‐glucan glucanohydrolase; EC 3.2.1.1) is produced with the non‐genetically modified Cellulosimicrobium funkei strain AE‐AMT by Amano Enzyme Inc. The food enzyme is free from viable cells of the production organism. It is intended to be used in starch processing for maltotriose production. Since residual amounts of total organic solids (TOS) are removed by purification steps applied during starch processing, the estimation of a dietary exposure is considered unnecessary. Genotoxicity tests did not indicate a safety concern. The systemic toxicity was assessed by means of a repeated dose 90‐day oral toxicity study in rats. The Panel identified a no observed adverse effect level at the highest dose of 230 mg TOS/kg body weight (bw) per day. Similarity of the amino acid sequence of the food enzyme to those of known allergens was searched and nine matches were found. The Panel considered that, under the intended conditions of use, the risk of allergic sensitisation and elicitation reactions by dietary exposure cannot be excluded, but the likelihood is considered low. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use.

16S rRNA gene identification of airborne pathogenic bacteria isolated from bioaerosols of wastewater treatment plant

Background and objective Wastewater treatment plants (WWTPs) represent a source of airborne bacteria. The presence of airborne bacteria in the environment of WWTPs could be considered as a potential health hazard for the exposed workers. This study aimed to isolate and identify cultivable bacteria from bioaerosols of different sites in a WWTP using 16S rRNA gene identification, as a first step to identify the pathogenic health hazards among the exposed workers.Materials and methods Air samples were collected from various locations in a selected WWTP. Airborne microorganism samples were collected on the nutrient agar plates by the settle-plate technique and were identified by the 16S rRNA gene sequencing technique.Results A total of 32 bacterial isolates were collected and sequenced. The study identified 25 different bacterial species. Of the 25 different strains, 10 (40%) belonged to pathogenic bacteria. Overall, 40% of the isolated pathogenic species were from the secretary room locations. The isolated bacterial species were Staphylococcus sp., Bacillus sp., Rhodococcus sp., Cellulosimicrobium funkei, Kytococcus sedentarius, and Kocuria rosea. The highest percentage occurrence was Bacillus sp. (37.5%), followed by Staphylococcus sp. (18.75%).Conclusions Disseminated infection can be associated with isolated pathogen, and this result gives a warning of the danger of the spread of pathogenic aerobic bacteria in WWTPs and their existence in indoor environments.

ХАРАКТЕРИСТИКА ПРЕДСТАВИТЕЛЯ РОДА CELLULOSIMICROBIUM КАК ДЕСТРУКТОРА 2,4-ДИХЛОРФЕНОКСИУКСУСНОЙ КИСЛОТЫ

On the basis of the cultural, morphological, physiological and biochemical features, the taxonomic position of the NPZ-121 strain (isolated from the soil contaminated with chemical waste in Ufa (Russia)) as belonging to the species Cellulosimicrobium funkei was specified. In a batch culture the dynamics of growth of the strain C. funkei NPZ-121 and utilization of 2,4-dichlorophenoxyacetic acid at a concentration of 100 mg/l were described. For 11 days the culture used up to 69% of the substrate from the initial value. The ability of the strain to metabolize 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) was revealed previously. Thus, the polysubstrate activity to chlorinated phenoxyacetic acids of the NPZ-121 strain was established.

Novel Bi-Modular GH19 Chitinase with Broad pH Stability from a Fibrolytic Intestinal Symbiont of Eisenia fetida, Cellulosimicrobium funkei HY-13.

Endo-type chitinase is the principal enzyme involved in the breakdown of N-acetyl-d-glucosamine-based oligomeric and polymeric materials through hydrolysis. The gene (966-bp) encoding a novel endo-type chitinase (ChiJ), which is comprised of an N-terminal chitin-binding domain type 3 and a C-terminal catalytic glycoside hydrolase family 19 domain, was identified from a fibrolytic intestinal symbiont of the earthworm Eisenia fetida, Cellulosimicrobium funkei HY-13. The highest endochitinase activity of the recombinant enzyme (rChiJ: 30.0 kDa) toward colloidal shrimp shell chitin was found at pH 5.5 and 55 °C and was considerably stable in a wide pH range (3.5–11.0). The enzyme exhibited the highest biocatalytic activity (338.8 U/mg) toward ethylene glycol chitin, preferentially degrading chitin polymers in the following order: ethylene glycol chitin > colloidal shrimp shell chitin > colloidal crab shell chitin. The enzymatic hydrolysis of N-acetyl-β-d-chitooligosaccharides with a degree of polymerization from two to six and colloidal shrimp shell chitin yielded primarily N,N′-diacetyl-β-d-chitobiose together with a small amount of N-acetyl-d-glucosamine. The high chitin-degrading ability of inverting rChiJ with broad pH stability suggests that it can be exploited as a suitable biocatalyst for the preparation of N,N′-diacetyl-β-d-chitobiose, which has been shown to alleviate metabolic dysfunction associated with type 2 diabetes.

Mass balance and kinetics of biodegradation of endocrine disrupting phthalates by Cellulosimicrobium funkei in a continuous stirred tank reactor system

This study investigated the potential ofCellulosimicrobium funkeifor degrading dimethyl phthalate (DMP) and diethyl phthalate (DEP). Effect of different initial concentrations of phthalates on their biodegradation and growth ofC. funkeiwas examined using shake flasks and a continuous stirred tank reactor (CSTR). Complete degradation of both DMP and DEP was achieved in CSTR, even up to 3000 and 2000 mg/L initial concentrations, respectively. Simultaneous degradation of the phthalates in mixture, i.e. more than 80% and 55% biodegradation efficiency were achieved at 1000 and 2000 mg/L initial concentrations of DMP and DEP, respectively, using the CSTR. Mass balance analysis of the degradation results suggested proficient degradation of DMP and DEP with biomass yield values of 0.64 and 0.712, respectively. The high values of inhibition constant Kiestimated using the Tessier and Edward substrate inhibition models indicated very good tolerance ofC. funkeitoward biodegradation of DMP and DEP.

Cellulosimicrobium composti sp. nov., a thermophilic bacterium isolated from compost.

A Gram-stain-positive, yellow-pigmented, non-motile actinobacterial strain, designated as BIT-GX5T, was isolated from a sesame husks compost collected in Beijing, PR China. This bacterium was found to be able to grow in the temperature range from 16 to 50 °C and had an optimal growth temperature at 45 °C. Its taxonomic position was analysed using a polyphasic approach. The 16S rRNA gene sequence (1482 bp) of strain BIT-GX5T was most similar to Cellulosimicrobium funkei ATCC BAA-886T (99.45%), Cellulosimicrobium cellulans LMG 16121T (99.17%) and Cellulosimicrobium marinum RS-7-4T (98.75%). The results of phylogenetic analyses, based on the 16S rRNA gene, concatenated sequences of five housekeeping genes (gyrB, rpoB, recA, atpD and trpB) and genome sequences, placed strain BIT-GX5T in a separate lineage among the genus Cellulosimicrobium within the family Promicromonosporaceae. The major polar lipids of strain BIT-GX5T were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, aminophospholipid and aminolipid. The major isoprenoid quinone was MK-9(H4), while the cell-wall sugars were galactose, rhamnose, glucose and mannose. The peptidoglycan type was A4α l-Lys-d-Ser-d-Asp. The major fatty acids were anteiso-C15:0 and iso-C15: 0, which were similar to other members in the genus Cellulosimicrobium. Results of in silico DNA-DNA hybridization and average nucleotide identity calculations plus physiological and biochemical tests exhibited the genotypic and phenotypic differentiation of strain BIT-GX5T from the other members of the genus Cellulosimicrobium. Therefore, strain BIT-GX5T is considered to represent a novel species within the genus Cellulosimicrobium, for which the name Cellulosimicrobium composti sp. nov. is proposed. The type strain is BIT-GX5T (= CGMCC 1.17687T = KCTC 49391T).

Cellulosimicrobium funkei strain AR6 alleviate Cr(VI) toxicity in Lycopersicon esculentum by regulating the expression of growth responsible, stress tolerant and metal transporter genes

Chromium (VI) [Cr(VI)] is the predominant environmental pollutant, which adversely affects the growth, physiology and molecular behaviour of the plants. Mitigation of Cr(VI) toxicity in plant by plant growth promoting rhizobacteria (PGPR) is an efficient inexpensive approach. Hence, the present study was designed to elucidate the influence of Cellulosimicrobium funkei AR6 strain on the growth, physico-chemical and transcriptional variations in Lycopersicon esculentum seedlings under Cr(VI) stress. In this study, Cr(VI) exposure reduced the root length (up to 55.50%), shoot length (up to 52.49%) and biomass (up to 57.29%) of L. esculentum, while strain AR6 inoculation significantly increased the above parameters. Moreover, Cr(VI) toxicity increased the production of stress markers such as proline and malondialdehyde (MDA) content in L. esculentum. However, inoculation of C. funkei AR6 strain reduced the production of proline and MDA levels. In gene expression studies, AR6 inoculation influenced the expression of cell wall proliferation LeEXP genes and stabilized the antioxidant system of L. esculentum seedlings by altering the expression of various stress marker genes such as P5CS, DHN, HSP and MT. Besides, strain AR6 down-regulated the major metal transporter NRAMP genes and consequently decreased the Cr accumulation in L. esculentum seedlings by 60.76 and 48.06% at 100 and 200 μg/ml of Cr(VI) treatment, respectively. Hence, these results suggest that C. funkei AR6 could alleviate Cr(VI) induced toxicity through improving the plant growth, stress tolerance and reducing metal accumulation in L. esculentum.

Genome sequence analysis and bioactivity profiling of marine-derived actinobacteria, Brevibacterium luteolum, and Cellulosimicrobium funkei.

Genome analysis gives important insights into the biosynthetic potential of marine actinobacteria. The genomes of two marine actinomycetes Brevibacterium luteolum MOSEL-ME10a and Cellulosimicrobium funkei MOSEL-ME6 were sequenced to identify the biosynthetic gene clusters (BGCs). Additionally, anti-proliferative, antioxidant, and enzyme inhibitory activities were studied in vitro. We report a total genome size of 2.77Mb with GC content of 67.8% and 6.81Mb with GC content of 69% for Brevibacterium sp. MOSEL-ME10a and Cellulosimicrobium sp. MOSEL-ME6, respectively. Biosynthetic gene clusters (BGCs) encoding different classes of natural products were predicted including terpenes, peptides, siderophores, ectoines, and bacteriocins. The bioactivity potential of crude extracts derived from these strains was evaluated. Notable anti-proliferative activity was observed against HepG2 cell line (hepatocellular carcinoma) with an IC50 value of 182µg/mL for Brevibacterium sp. MOSEL-ME10a. Furthermore, antioxidant activity was assessed with IC50 values of 48.91µg/mL and 102.5µg/mL for Brevibacterium sp. MOSEL-ME10a and Cellulosimicrobium sp. MOSEL-ME6, respectively. Protein kinase inhibition potential was observed only for Brevibacterium sp. MOSEL-ME10a. Our study also reports lower amylase enzyme inhibition potential for both strains. Moreover, both crude extracts showed only slight-to-no toxic effect on erythrocytes at 400µg/mL and below, indicating erythrocyte membrane stability. Our data present the genomic features revealing biosynthetic potential of marine actinobacteria as well as biological activities found in vitro.

New insights into the biodegradation of chlorpyrifos by a novel bacterial consortium: Process optimization using general factorial experimental design

Himalayan mountains are subjected to the intensive and unjudicial application of chlorpyrifos (CP) in agricultural practices; hence it has spurred concerns over food safety and environmental consequences. These low-temperature mountainous regions are foremost ecosystems, representing the large-scale distribution of cold trapped CP residues. A bacterial consortium ECO-M was formed by isolating the CP degrading bacterial strains viz Agrobacterium tumefaciens strain ECO1, Cellulosimicrobium funkei strain ECO2, Shinella zoogloeoides strain ECO3 and Bacillus aryabhattai strain ECO4. At an initial concentration of 50 mg L−1, consortium ECO-M degraded 100% of CP within 6 days. Emergence and subsequent degradation of the two metabolites, 3, 5, 6-trichloro-2-pyridinol (TCP) and 2-hydroxypyridine were confirmed by GC-MS analysis. A degradation pathway of CP by isolated strains has been proposed. A general factorial experimental design was effectuated to prognosticate the optimum biodegradation by manifesting the optimal biological and physicochemical factors. Fitness of the experimental design was affirmed experimentally by employing optimized factors i.e., temperature 30 °C, CP concentration 50 mg L−1 and an inoculum size of 10% (v/v). The model appropriacy and the rationality of the optimization procedure were appraised by installing an in-situ microcosms experiment using the real contaminated soil collected from the Himalayan mountain ecosystem. The augmentation culture seems to be effectively conspicuous in stimulating maximum degradation up to 94.3% in the CP contaminated soil.

Characterization of xanthine oxidase from Cellulosimicrobium funkei possessing hypoxanthine-metabolizing activity.

Purine-degrading enzymes are favourable as medications and diagnostic tools for hyperuricemia. This study aimed to characterize enzymes isolated from micro-organisms, which may be useful for developing a new prophylaxis for hyperuricemia. Cellulosimicrobium funkei A153 was found to be a good catalyst for hypoxanthine degradation and could oxidize hypoxanthine to xanthine and further to uric acid. The enzyme catalysing this oxidation was purified, and its partial amino acid sequences were examined. Based on this information and genome sequencing results, this xanthine dehydrogenase family protein was cloned and expressed in Rhodococcus erythropolis L88. The recombinant enzyme with a His-tag was characterized. The enzyme was a xanthine oxidase as it could utilize molecular oxygen as an electron acceptor. It was stable under 50°C and exhibited maximum activity at pH 7·0. The kcat , Km and kcat /Km values for xanthine were 1·4s-1 , 0·22mmoll-1 and 6·4s-1 mmol-1 l, respectively. Xanthine oxidase is favourable for hyperuricemia medication because it oxidizes hypoxanthine, an easily adsorbed purine, to xanthine and further to uric acid, which are hardly adsorbed purines. The enzyme is useful for decreasing serum uric acid levels via conversion of easily absorbed purines to hardly absorbed purines in the intestine. Enzymes from micro-organisms may be used as a novel prophylaxis for hyperuricemia.