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One hundred tree species from 4 different forest types (25 from each forest) of the Western Ghats were studied for the occurrence of Pestalotiopsis as foliar endophytes. Morphological and ITS sequence study confirmed that species of Pestalotiopsis are generalist endophytes infecting taxonomically unrelated tree hosts. Furthermore, a single tree species harboured more than one species of this endophyte. Considering the leaf as a microhabitat, such a wide ecological amplitude of Pestalotiopsis as a foliar endophyte appears to be the result of accumulation of a suite of traits which are governed by the environment. This could be one of the reasons for the existence of generalist fungi among endophytes transcending host taxonomic and habitat restrictions. [ABSTRACT FROM AUTHOR]

Abstract: To enhance the fertilizer value of rock phosphate in alkaline soils, the phosphate (P) solubilizing fungus Penicillium oxalicum was isolated from the rhizosphere soil of rock phosphate mine landfills and tested for its efficacy to solubilize rock phosphate (RP) as well as promotion of the growth of wheat and maize plants grown in soil amended with RP. The results showed that P. oxalicum effectively solubilized RP in Pikovskaya’s medium and released higher amount of phosphorus. The solubilization was increased with increase in concentration of RP. Field experiments showed that inoculation of P. oxalicum significantly increased the growth and yield of two consecutive crops i.e. wheat and maize compared to the control soil. The P content was significantly increased in the plants. The available P and organic carbon levels increased in RP amended soil inoculated with P. oxalicum compared to the control soil. It was found that the P. oxalicum along with RP can substitute the chemical fertilizer in alkaline soil and help in improving the crop production. [ABSTRACT FROM AUTHOR]

[Display omitted] • Effect of nsSNP on structure and functions of GPI-T subunit GPI8p of P. falciparum was studied. • GPI8p was analyzed using various sequence based and structure based computational tools. • Deleterious nsSNPs were identified in the GPI8p of P. falciparum. • COACH server revealed no mutation at the predicted ligand binding site. • GPI8p serves as a novel target for anti-malarial drugs and provides details for experimentation. Drug resistance is increasingly evolving in malaria parasites; hence, it is important to discover and establish alternative drug targets. In this context, GPI-anchor transamidase (GPI-T) is a potential drug target primarily of its crucial role in the development and survival of the parasite in the GPI anchor biosynthesis pathway. The present investigation was undertaken to explore the plausible effects of nsSNP on the structure and functions of GPI-T subunit GPI8p of Plasmodium falciparum. The GPI8p (PF3D7_1128700) was analyzed using various sequence-based and structure-based computational tools such as SIFT, PROVEAN, PredictSNP, SNAP2, I-Mutant, MuPro, ConSurf, NetSurfP, MUSTER, COACH server and STRING server. Of the 34 nsSNPs submitted for functional analysis, 18 nsSNPs (R124 L, N143 K, Y145 F, V157I, T195S, K379E, I392 K, I437 T, Y438H, N439D, Y441H, N442D, N448D, N451D, D457A, D457Y, I458 L and N460 K) were predicted to have deleterious effects on the protein GPI8p. Additionally, I-Mutant 2.0 and MuPro both showed a decrease in stability after mutation as a result of these nsSNPs, suggesting the destabilization of protein. ConSurf findings suggest that most of the regions were highly conserved. In addition, COACH server was used to predict the ligand binding sites. It was found that no mutation was present at the predicted ligand binding site. The results of the STRING database showed that the protein GPI8p interacts with those proteins which either involve the biosynthetic process of attaching GPI anchor to protein or GPI anchor. The present study suggested that the GPI8p could be a novel target for anti-malarial drugs, which provides significant details for further experimentation. [ABSTRACT FROM AUTHOR]

Arsenic (As) contamination is one of the most daunting environmental problem bothering the whole world. Exploring a suitable bioremediation technique is an urgent need of the hour. The present study focusses on scrutinizing the ectomycorrhizal (ECM) fungus for its potential role in As detoxification and understanding the molecular mechanisms responsible for its tolerance. When exposed to increasing concentrations of external As, the ECM fungus H. cylindrosporum accumulated the metalloid intracellularly, inducing the glutathione biosynthesis pathway. The genes coding for GSH biosynthesis enzymes, γ-glutamylcysteine synthetase (Hcγ-GCS) and glutathione synthetase (HcGS) were highly regulated by As stress. Arsenic coordinately upregulated the expression of both Hcγ-GCS and HcGS genes, thus resulting in increased Hcγ-GCS and HcGS protein expressions and enzyme activities, with substantial increase in intracellular GSH. Functional complementation of the two genes (Hcγ-GCS and HcGS) in their respective yeast mutants (gsh1 Δ and gsh2 Δ ) further validated the role of both enzymes in mitigating As toxicity. These findings clearly highlight the potential importance of GSH antioxidant defense system in regulating the As induced responses and its detoxification in ECM fungus H. cylindrosporum. Image 1 • Glutathione biosynthesizing genes, Hc γ -GCS and HcGS were characterized in H. cylindrosporum. • Enhanced accumulation and glutathione content were observed due to As exposure. • Yeast mutants rescued the As sensitivity due to cloning of Hc γ -GCS and HcGS. • mRNA accumulation of Hc γ -GCS and HcGS increased significantly due to As exposure. • Glutathione play an important role in As detoxification in ECM fungus H. cylindrosporum. [ABSTRACT FROM AUTHOR]

Three isolates of Aspergillus tubingensis and two isolates of Aspergillus niger isolated from rhizospheric soils were tested on solubilization of different rock phosphates. All the isolates of Aspergillus were capable of solubilizing all the natural rock phosphates. A. tubingensis (AT1) showed maximum percent solubilization in all the rock phosphates tested in this study when compared to other isolates. This isolate also showed highest phosphorus (P) solubilization when grown in the presence of 2% of rock phosphate. A. tubingensis (AT1) seems to be more efficient in solubilization of rock phosphates compared to other isolates reported elsewhere. This is the first report of rock phosphate solubilization by A. tubingensis and might provide an efficient large scale biosolubilization of rock phosphates intended for P fertilizer. [Copyright &y& Elsevier]

Abstract: Phenotypic mutants of Aspergillus tubingensis were obtained by UV irradiation and phosphate solubilization ability of these mutants were studied and compared with the wild type strain. Low phosphate solubilizing mutant was also selected in this study. Among the different mutants, AtM-5 and AtM-2 showed highest P solubilization when tri-calcium phosphate and rock phosphate were used as P source compared to the wild type strain and other mutants. These mutants also showed maximum acid phosphatase and phytase activity. These results suggest that P solubilization by these isolates is due to lowering of pH of the culture filtrate and also the activity of acid phosphatase and phytase. [Copyright &y& Elsevier]

Highlights • Sulfate attack (chemical and physical) causes severe damage to concrete structures. • Surface deterioration & strength loss of concrete was not found in bacteria treated specimens. • Mortars showed no surface scaling and salt efflorescence due to bacterial treatment. • Bacteria improved the lifecycle performance of concrete in sulfate environment. Abstract Application of microbial induced calcium carbonate precipitation (MICP) via biomineralization process has been considered as a novel method in improving durability properties of concrete. This bio-based treatment had been extensively targeted to improve the overall performance of concrete at lab scale experiments. Durability of microbial treated concrete under aggressive environments is still unexplored. In the current study, the durability properties of microbial treated concrete structures were studied after exposure to chemical and physical sulfate salt solutions (5% Na 2 SO 4 and 5% MgSO 4). It has been observed that sulfate attack damaged the untreated concrete specimens causing ultimate failure due to expansion under both exposure regimes. Thick salt efflorescence and severe surface scaling was observed in untreated mortar during physical sulfate attack. However, specimens treated with bacteria (Bacillus sp. CT5) significantly improved the resistance towards sulfate ingress. The experimental results indicate the extensive reduced expansion rate, salt efflorescence and surface scaling in bacterial treated concrete in sulfate exposure. The present study results indicates the potential of this technology in the overall improved resistance of microbial concrete against sulfate environment. [ABSTRACT FROM AUTHOR]

Abstract: This study concerns the thermotolerance of spores of mesophilic fungi isolated from a tropical semi-arid habitat subject to dry season fire in the Western Ghats, southern India. Among 25 species of Ascomycota isolated from leaf litter, nine were able to grow after incubation in a drying oven for 2h at 100°C; the spores of two of these species survived 2h incubation at 110°C, and one survived exposure to 115°C for 2h. The range of thermotolerance among mesophilic fungi isolated from the leaf litter was surprising: filamentous fungi from other habitats, including species that colonize scorched vegetation after fires and thermophilic forms occurring in self-heating plant composts, cannot survive even brief exposure to such high temperatures. It is possible that the exceptional heat resistance of the Indian fungi is related to adaptations to surviving fires. Genetic analysis of the physiological mechanisms of heat resistance in these fungi offers prospects for future biotechnological innovations. The discovery of extreme thermotolerance among common saprotrophs shows that this physiological trait may be more widespread than recognized previously, adding to concern about the evolution of opportunistic pathogens on a warmer planet. The fungi in this study are among the most heat-resistant eukaryotes on record and are referred to here as ‘Agni’s Fungi’, after the Hindu God of Fire. [Copyright &y& Elsevier]

Various anthropogenic activities attribute to the addition and accumulation of heavy metals in soil which creates an environment unsuitable for all organisms. Despite such conditions, some microbial populations are able to survive and grow due to functioning of certain genes. Investigating the role of eukaryotic microbes in metal contaminated soil was the focus of this study. Culture independent approach was employed and size fractionated eukaryotic cDNA libraries (library A < 0.5 kb, library B 0.5–1.0 kb, and library C 1.0–4.0 kb) of soil were constructed from soil RNA and were screened for cadmium (Cd) tolerance by functional complementation assay by using Cd sensitive yeast mutant ycf1 Δ . Screening of the library C yielded clones capable of growing in presence of Cd amended media. In the present study, one of the clones, PLCg49 was selected because of its ability to grow at high concentrations of Cd (40–100 μM). PLCg49 was also found to be highly inducible in presence of Cd where the highest fold expression was observed at 60 μM of Cd. Sequence analysis of PLCg49 showed homology with Serine Protease Inhibitor (Serpin) of the eukaryote Hypsibius dujardini. Serpins are a broad family of protease inhibitors which are majorly stress-inducible genes usually triggered by biotic and abiotic stresses and help in maintaining cell viability. Copper-sensitive (cup1 Δ ), Zn-sensitive (zrc1 Δ ) and Cobalt-sensitive (cot 1 Δ ) yeast mutants rescued their sensitivity when transformed with PLCg49, indicating its tolerance to different heavy metals. The protease sensitive yeast mutant (pbi2 Δ ) transformed with PLCg49 protected from the cell lysis when grown in presence of trypsin and proteinase K confirming the role of PLCg49 as an effective serpin. Present study results suggested that PLCg49 serves as a potential metal tolerant gene, helping us to understand new pathways participating in metal tolerance. Image 1 • Sized eukaryotic cDNA libraries were constructed from metal contaminated soil. • Cd tolerant PLCg49 clone homologous to serine protease inhibitor was characterized. • Metal sensitive yeast mutants carrying PLCg49 rescued their metal sensitivity. • PLCg49 protected the yeast cell lysis in presence of trypsin and proteinase K. • PLCg49 serves as bioremediating agent and biomarker in metal contaminated sites. [ABSTRACT FROM AUTHOR]