Proteomic Perspective of Cadmium Tolerance in Providencia rettgeri Strain KDM3 and Its In-situ Bioremediation Potential in Rice Ecosystem.

In this study, a multi-metal-tolerant natural bacterial isolate Providencia rettgeri strain KDM3 from an industrial effluent in Mumbai, India, showed high cadmium (Cd) tolerance. Providencia rettgeri grew in the presence of more than 100 ppm (880 µM) Cd (LD50 = 100 ppm) and accumulated Cd intracellularly. Following Cd exposure, a comparative proteome analysis revealed molecular mechanisms underlying Cd tolerance. Among a total of 69 differentially expressed proteins (DEPs) in Cd-exposed cells, de novo induction of ahpCF operon proteins and L-cysteine/L-cystine shuttle protein FliY was observed, while Dps and superoxide dismutase proteins were overexpressed, indicating upregulation of a robust oxidative stress defense. ENTRA1, a membrane transporter showing homology to heavy metal transporter, was also induced de novo. In addition, the protein disaggregation chaperone ClpB, trigger factor, and protease HslU were also overexpressed. Notably, 46 proteins from the major functional category of energy metabolism were found to be downregulated. Furthermore, the addition of P. rettgeri to Cd-spiked soil resulted in a significant reduction in the Cd content [roots (11%), shoot (50%), and grains (46%)] of the rice plants. Cd bioaccumulation of P. rettgeri improved plant growth and grain yield. We conclude that P. rettgeri, a highly Cd-tolerant bacterium, is an ideal candidate for in-situ bioremediation of Cd-contaminated agricultural soils.

Long-term outcome of treatment of vertebral body hemangiomas with direct ethanol injection and short-segment stabilization.

BACKGROUND: Vertebral body hemangiomas with myelopathy are difficult to manage. OBJECTIVE: The objective of this study was to evaluate the role of intraoperative ethanol embolization, surgical decompression, and instrumented short-segment fusion in vertebral hemangioma (VH) with myelopathy and long-term outcome (>24 months). CLINICAL MATERIALS AND METHODS: This prospective study included symptomatic VH with cord compression with myelopathy. Pathologic fractures and deformity or multilevel pathologies were excluded from the study. Surgery consisted of intraoperative bilateral pedicular absolute alcohol (<1% hydrated ethyl alcohol) injection, laminectomy, and cord decompression at the level of pathology followed by a short-segment instrumented fusion using pedicle screws. RESULTS: The study included 33 patients (mean 26.9±13.2, range: 10-68 years, 18 females). The clinical features of the study were myelopathy in all patients (5 paraplegic), sphincter involvement (13), and mid back or lower back pain (7). The preoperative American Spinal Injury Association (ASIA) scores were A (7), B (11), C (6), D (8), and E (1). Majority of the patients had single vertebral involvement (30) and three patients had multiple-level involvement. Six patients underwent surgery earlier (one underwent alcohol embolization). The mean surgical time was 124±39 minutes, and the average blood loss was 274±80 cc. The mean amount of absolute alcohol injected was 14.6±5.7 cc (two patients required 20 and 25 cc). Immediate embolization was achieved in all patients, allowing laminectomy and easy removal of soft-tissue hemangioma. Post surgery, one patient had transient deterioration, and the condition of the rest of the patients improved (sphincters improved in nine patients) at a follow-up ranging 28-103 months (mean 47.6±22.3). Follow-up ASIA scores were E (26), D (4), B (2), and C (1). All patients showed evidence of bone sclerosis and relief of cord compression on follow-up imaging. CONCLUSIONS: This is the largest study in literature showing excellent improvement, low reoperation rates after ethanol embolization, and short-segment fixation.

Management of Pediatric Posterior Circulation Aneurysms-12-Year Single-Institution Experience.

BACKGROUND: Pediatric posterior circulation aneurysms are rare, complex, poorly understood lesions on which only limited literature is currently available. We report our 12-year experience of managing this condition to enhance knowledge of this rare entity. METHODS: Patients <18 years old with posterior circulation aneurysms managed at our institution from January 2005 to April 2017 were included. Demographic, clinical, radiologic and management details were retrieved from hospital records and characteristics of the aneurysms and treatment were analyzed. RESULTS: During this period, 20 pediatric patients (male-to-female ratio 15:6; mean age, 13.1 years) with posterior circulation aneurysms were treated. Most of the patients (75%) presented with subarachnoid hemorrhage. The most common location was the vertebrobasilar junction and vertebral artery (31.81%) followed by the basilar artery and the posterior cerebral artery (27.72% each). Dissecting (81.8%) and large (63.63%) aneurysms were the most common types noted. Of the15 patients with 22 aneurysms treated, 13 underwent endovascular management (parent vessel sacrifice in 8 aneurysms and parent vessel preservation in 5 aneurysms), 1 patient underwent surgery, and 1 patient received medical management for central nervous system tuberculosis. During follow-up, 1 patient had recurrence of aneurysm, and 1 patient died after discharge from the hospital. Overall good outcome was recorded in 90% of patients (Glasgow Outcome Scale score 4-5). CONCLUSIONS: Vertebrobasilar junction and vertebral artery was the most common location for posterior circulation aneurysms and most were dissecting aneurysms. Endovascular treatment was the mainstay of management. Overall good outcome was observed at long-term follow-up.

Isolation and characterization of microalgae for biodiesel production from Nisargruna biogas plant effluent.

Increasing energy demand and depleting fossil fuel sources have intensified the focus on biofuel production. Microalgae have emerged as a desirable source for biofuel production because of high biomass and lipid production from waste water source. In this study, five microalgae were isolated from effluents of Nisargruna biogas plants. These isolates were identified based on morphology and partial 18S and 23S rRNA gene sequences. Growth and lipid accumulation potential of these microalgae were investigated. One isolate, Chlorella sp. KMN3, accumulated high biomass (1.59 ± 0.05 g L(-1)) with moderate lipid content (20%), while another isolate Monoraphidium sp. KMN5 showed moderate biomass accumulation of 0.65 ± 0.05 g L(-1) with a very high (35%) lipid content. The fatty acid methyl esters mainly composed of C-16:0, C-18:0, C-18:1 and C-18:2. This observation makes these microalgae immensely potential candidate for biodiesel production using the effluent of a biogas plant as feed stock.

Analysis of changing paradigms of management in 179 patients with spinal tuberculosis over a 12-year period and proposal of a new management algorithm.

OBJECTIVE: To describe management and outcome in a large cohort of patients with spinal tuberculosis (TB). METHODS: Of 212 patients with spinal TB treated between January 1999 and June 2011, 179 patients were included in the study (≥6 months follow-up; mean age, 34.8 years; age range, 10-75 years). The cohort was divided into two groups (n = 89 and n = 90); group I was treated from 1999-2003, and group II was treated from 2004-2011. RESULTS: The study cohort comprised 93 male patients. Mean age was 34.8 years ± 7.2 (range, 10-75 years). Mean duration of symptoms was 2.4 months. Sensorimotor deficits were present in 167 patients (93.5%; 74 patients were paraplegic), pain was present in 156 patients (87%), bladder involvement was present in 127 patients (71.7%), and extraspinal TB was present in 36 patients (22.3%). Of patients, 92% were receiving prior chemotherapy; one fifth of these patients were on second-line chemotherapy. Thoracic spine involvement was most common (n = 86; 57%), followed by cervical spine (n = 50; 29%), craniovertebral junction (n = 22; 15%), and lumbosacral spine (n = 20; 10.5%). Surgery was performed in 146 patients (68% instrumented fusions and 16% circumferential fusions). Mean follow-up was 20.2 months (range, 6-60 months). Sensorimotor deficits improved in 89% of patients, pain improved in 71%, bladder symptoms improved in 88%, and paraplegia improved in 77%. Patients in group II had a higher incidence of cord compression (P < 0.01), severe vertebral body collapse (P < 0.001), and paraplegia (P < 0.001). Group II patients underwent more instrumented surgeries (P < 0.01), especially circumferential fusions (P < 0.001). The improvement in paraplegia was better after 2004 (group II). Bladder symptoms correlated with the timing of surgery (P < 0.1). CONCLUSIONS: Medical treatment of spinal TB is the mainstay; however, radical, instrumented surgeries should be offered when indicated. The presence of paraplegia should not preclude surgery. A practical management paradigm is also suggested.

Enhanced tolerance and remediation of anthracene by transgenic tobacco plants expressing a fungal glutathione transferase gene.

Plants can be used for remediation of polyaromatic hydrocarbons, which are known to be a major concern for human health. Metabolism of xenobiotic compounds in plants occurs in three phases and glutathione transferases (GST) mediate phase II of xenobiotic transformation. Plants, although have GSTs, they are not very efficient for degradation of exogenous recalcitrant xenobiotics including polyaromatic hydrocarbons. Hence, heterologous expression of efficient GSTs in plants may improve their remediation and degradation potential of xenobiotics. In the present study, we investigated the potential of transgenic tobacco plants expressing a Trichoderma virens GST for tolerance, remediation and degradation of anthracene-a recalcitrant polyaromatic hydrocarbon. Transgenic plants with fungal GST showed enhanced tolerance to anthracene compared to control plants. Remediation of (14)C uniformly labeled anthracene from solutions and soil by transgenic tobacco plants was higher compared to wild-type plants. Transgenic plants (T(0) and T(1)) degraded anthracene to naphthalene derivatives, while no such degradation was observed in wild-type plants. The present work has shown that in planta expression of a fungal GST in tobacco imparted enhanced tolerance as well as higher remediation potential of anthracene compared to wild-type plants.

Expression of a human cytochrome P4502E1 in Nicotiana tabacum enhances tolerance and remediation of γ-hexachlorocyclohexane.

Lindane (γ-hexachlorocyclohexane), a persistent organo-chlorine insecticide widely used in developing countries, has a negative effect as a polluting agent of soil and surface waters. Plants can be used for remediation of organic pollutants and their efficiency can be enhanced by introduction of heterologous genes. Mammalian cytochrome P4502E1 (CYP2E1), an important monooxygenase is involved in the degradation of a wide range of xenobiotics including environmental pollutants/herbicides and pesticides. Here, we report the development of transgenic tobacco plants expressing human CYP2E1 and the efficacy of plants for remediation of lindane. Transgenic tobacco plants with CYP2E1 showed enhanced tolerance to lindane when grown in hydroponic medium and soil compared to control plants. Remediation of (14)C-labeled lindane from hydroponic medium was higher in transgenic plants compared to that of control plants, with the best performing line showing 25% higher removal of lindane from solution than control plants. Similar results were seen in plants grown in soil spiked with lindane. The present study has shown that transgenic plants expressing CYP2E1 gene have potential use for remediation of lindane from contaminated solutions and soil.

Performance of electron acceptors in catholyte of a two-chambered microbial fuel cell using anion exchange membrane.

The performance of the cathodic electron acceptors (CEA) used in the two-chambered microbial fuel cell (MFC) was in the following order: potassium permanganate (1.11V; 116.2 mW/m(2))>potassium persulfate (1.10 V; 101.7 mW/m(2))>potassium dichromate, K(2)Cr(2)O(7) (0.76 V; 45.9 mW/m(2))>potassium ferricyanide (0.78 V; 40.6 mW/m(2)). Different operational parameters were considered to find out the performance of the MFC like initial pH in aqueous solutions, concentrations of the electron acceptors, phosphate buffer and aeration. Potassium persulfate was found to be more suitable out of the four electron acceptors which had a higher open circuit potential (OCP) but sustained the voltage for a much longer period than permanganate. Chemical oxygen demand (COD) reduction of 59% was achieved using 10mM persulfate in a batch process. RALEX™ AEM-PES, an anion exchange membrane (AEM), performed better in terms of power density and OCP in comparison to Nafion®117 Cation Exchange Membrane (CEM).

Overlapping and distinct functions of two Trichoderma virens MAP kinases in cell-wall integrity, antagonistic properties and repression of conidiation.

We have studied the functions of the Trichoderma virens TmkB, a homologue of the yeast cell-wall integrity MAP kinase Slt2, using gene knockout. The functions of TmkB were compared to those of the pathogenicity MAP kinase homologue (TmkA). Like the tmkA loss-of-function mutants, tmkB mutants exhibited reduced radial growth and constitutive conidiation in dark as well as in liquid shake cultures. The tmkB mutants, in contrast to tmkA mutants, had cell-wall integrity defects, as shown by autolysis of the mycelia and increased sensitivity to cell-wall degrading enzymes. Interestingly, the tmkB mutants were not autolytic on the synthetic Vogels minimal medium. The tmkB mutants had attenuated ability to overgrow the plant pathogen Sclerotium rolfsii, while retaining the ability to overgrow Rhizoctonia solani and Pythium spp., a phenotype also exhibited by the tmkA mutants. This first functional analysis of a cell-wall integrity MAPK in Trichoderma spp., a group of economically important fungi, shows the importance of this signaling pathway in biocontrol. Common phenotypes of the TmkA and TmkB pathways suggest that the two MAPKs may share some substrates, perhaps subunits of key transcription factors, thus dependent on two phosphorylation events for their activity.

cAMP signalling is involved in growth, germination, mycoparasitism and secondary metabolism in Trichoderma virens.

An adenylate-cyclase-encoding gene, tac1, of Trichoderma virens, a soil fungus used in the biocontrol of plant pathogens, has been cloned and sequenced. The tac1 ORF spanned 7032 bp, encoding a protein of 2153 aa, which shared an identity of 65 % with the adenylate cyclase of Colletotrichum lagenarium. Deletion of tac1, through double-crossover homologous recombination, lowered the intracellular cAMP levels to below the detection limit. The mutants showed only 5-6 % of the wild-type growth rate on agar, but grew normally in shake culture. The mutants did not sporulate in darkness, and the spores failed to germinate in water. In the confrontation assay, the mutants did not overgrow the test plant pathogens Sclerotium rolfsii, Rhizoctonia solani and Pythium sp. Against Pythium sp., the mutants produced a clear zone of inhibition in the confrontation assay. HPLC analysis and bioassay showed reduced secondary metabolite production in the mutants. Using suppression subtractive hybridization (SSH), the genes that were underexpressed in the mutants were identified. Based on an array of 53 SSH library clones, 11 clones were identified as strongly downregulated in the Deltatac1 mutants; of these 11 clones, nine sequences were homologous to secondary metabolism-related gene sequences. Therefore, cAMP signalling positively regulates secondary metabolism in T. virens. This is believed to be the first direct genetic study on the role of cAMP signalling in a Trichoderma sp. Tac1 is also believed to be the first regulatory protein to be identified in T. virens that is involved in growth, germination, mycoparasitism and secondary metabolism.