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A very high level of alkalophilic and thermostable pectinase and xylanase has been produced from newly isolated strains of Bacillus subtilis and Bacillus pumilus respectively. Enzyme production for pectinase was carried out under SSF using combinations of cheap agricultural residues while xylanase was produced under submerged fermentation using wheat bran as substrate to minimize the cost of production of these enzymes Among the various substrates tested, the highest yield of pectinase production was observed by using combination of WB + CW (6592 U/g of dry substrate) supplemented with 4% yeast extract when incubated at 37 degrees C for 72 h using deionized water of pH 7.0 as moistening agent. The biobleaching effect of these cellulase free enzymes on kraft pulp was determined. Both xylanase and pectinase showed stability over a broad range of pH from 6 to 10 and temperature from 55 to 70 degrees C. The bleaching efficiency of the pectinase and xylanase on kraft pulp was maximum after 150 min at 60 degrees C using enzyme dosage of 5 IU/ml of each enzyme at 10% pulp consistency with about 16% reduction in kappa number and 84% reduction in permanganate number. Enzyme treated pulp when subjected to CDED(1)D(2) steps, 25% reduction in chlorine consumption and upto 19% reduction in consumption of chlorine dioxide was observed for obtaining the same %ISO brightness. Also an increase of 22 and 84% in whiteness and fluorescence respectively and a decrease of approximately 19% in the yellowness of the biotreated pulp were observed by pretreatment of the pulp with our enzymatic mixture.

Pectinase production from Bacillus subtilis SS was optimized under solid-state fermentation (5,943 U/g of dry bacterial bran). The pectinase produced was stable in neutral to alkaline pH range at 70 degrees C; therefore, the suitability of this pectinase in pulp and paper industry was investigated. The enzyme pretreatment process was optimized, and a pectinase dose of 5 IU/g of oven-dried pulp (10% consistency) at pH 9.5 temperature 70 degrees C after 150 min of treatment gave the best pretreatment to the pulp. An increase of 4.3% in brightness along with an increase of 14.8 and 65.3% in whiteness and fluorescence, respectively, whereas a 15% decrease in the yellowness of the pretreated pulp were observed. There was a 5.85% reduction in kappa number and 6.1% reduction in permanganate number along with a reduction in the chemical oxygen demand value. Significant characteristics showed by pectinase open new possibilities of application of this cellulase-free enzyme in the pulp and paper industry by reducing the negative environmental impact of chemicals apart from improving the properties of paper.

A cytosolic protein was purified from Escherichia coli BL21 that demonstrated potent antifungal activity against pathogenic strains of Aspergillus fumigatus, Aspergillus flavus, Aspergillus niger and Candida albicans. The MIC of purified protein from E. coli BL21 (PPEBL21) against Aspergillus species and C. albicans was 1.95-3.98 and 15.62 mg ml "1 , respectively. In vitro toxicity tests demonstrated no cytotoxicity of PPEBL21 to human erythrocytes up to the tested concentrations of 1250 mg ml "1. Amphotericin B was lethal to 100 % of human erythrocytes at a concentration of 37.5 mg ml "1 . The N-terminal amino acid sequence of PPEBL21 was found to be DLAEVASR, which showed 75 % sequence similarity with alcohol dehydrogenase of yeast. Mass fingerprinting by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry also substantiated these observations. The results suggested that E. coli BL21 might be an important bioresource of lead molecules for developing new peptide-based therapies for treating fungal infections.

Aims: To investigate the anti-Aspergillus properties of bacterial products. Methods and Results: In the present study, 12 bacterial strains were screened for antifungal activity against Aspergilli. The culture supernatant and lysates of Pseudomonas aeruginosa, Bacillus cereus, Escherichia coli (BL21, DH5a, HB101, XL Blue), Klebsiella pneumoniae, Streptomyces thermonitrificans, Streptococcus pneumoniae, Enterobacter aerogenes, Staphylococcus aureus and Salmonella typhi were examined for antifungal activity in protein concentration ranging from 1000AE0 to 7AE8 lg ml )1 using microbroth dilution assay. The lysate of Salm. typhi and E. coli BL21 exhibited the maximum activity against Aspergillus fumigatus, Aspergillus flavus and Aspergillus niger. Their in vitro minimum inhibitory concentrations (MICs) were found to be 15AE6-31AE2 lg ml )1 by microbroth dilution and spore germination inhibition assays. In disc diffusion assay, a concentration of 3AE1 lg disc )1 of Salm.typhi lysate showed significant activity against Aspergilli. Escherichia coli BL21 exhibited similar activity at 6AE2 lg disc )1 . The work on identification of molecule endowed with antimycotic properties is in progress. Conclusion:The products of Salm. typhi and E. coli demonstrated significant activity against Aspergillus species. Significance and Impact of the Study: This is the first time that E. coli has been reported for anti-Aspergillus activity. It could be an important source of biologically active compounds useful for developing better new antifungal drugs/or probiotics.

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This article documents the addition of 268 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Alburnoides bipunctatus, Chamaerops humilis, Chlidonias hybrida, Cyperus papyrus, Fusarium graminearum, Loxigilla barbadensis, Macrobrachium rosenbergii, Odontesthes bonariensis, Pelteobagrus vachelli, Posidonia oceanica, Potamotrygon motoro, Rhamdia quelen, Sarotherodon melanotheron heudelotii, Sibiraea angustata, Takifugu rubripes, Tarentola mauritanica, Trimmatostroma sp. and Wallago attu. These loci were cross-tested on the following species: Alburnoides fasciatus, Alburnoides kubanicus, Alburnoides maculatus, Alburnoides ohridanus, Alburnoides prespensis, Alburnoides rossicus, Alburnoides strymonicus, Alburnoides thessalicus, Alburnoides tzanevi, Carassius carassius, Fusarium asiaticum, Leucaspius delineatus, Loxigilla noctis dominica, Pelecus cultratus, Phoenix canariensis, Potamotrygon falkneri, Trachycarpus fortune and Vimba vimba.

The products of various strains of Escherichia coli (BL21, DH5AE, HB101 and XL Blue) were investigated for antimycotic properties using pathogenic isolates of Aspergillus. Co-culture experiments revealed that E. coli strains exhibited variable activity against Aspergillus fumigatus. The lysates prepared from DH5AE, HB101 and XL Blue strains of E. coli showed inhibitory activity against A. fumigatus in the protein concentration range of 62 . 50 to 250 . 00 ìg ml À1 . The highest activity was seen in the lysate of BL21, which inhibited the growth of A. fumigatus and Aspergillus flavus completely at a concentration of 31 . 25 ìg protein ml À1 . The MIC of BL21 lysate against Aspergillus niger was found to be 62 . 50 ìg ml À1 . The in vitro toxicity of BL21 lysate was evaluated using a haemolytic assay. A BL21 lysate protein concentration of 1250 . 00 ìg ml À1 was found to be nontoxic to human erythrocytes. The standard drug amphotericin B lysed 100 % of erythrocytes at a concentration of 37 . 50 ìg ml À1 . SDS-PAGE showed the presence of at least 15 major proteins in the lysate of BL21. Ion-exchange chromatography resolved the BL21 lysate into five fractions and fraction III was found to be endowed with anti-Aspergillus properties. The MIC of this fraction was found to be 3 . 90 ìg ml À1 . Further work on the purification of the active molecule and its characterization is in progress. INTRODUCTIONInfections due to opportunistic fungal pathogens such as Aspergillus and Candida species are emerging as major causes of morbidity and mortality in immunocompromised patients despite widespread use of several antifungal drugs Richardson & Kokki, 1998). The antifungal agents currently available for treatment of these infections include amphotericin B and its liposomal formulations, 5-fluorocytosine, triazoles and allylamines, which are used singly or in combination (Maertens et al., 2002;Chiou et al., 2000). These drugs not only have limited efficacy, all of them induce severe toxicity or immunosuppression (Georgopapadakou & Walsh, 1996). Further, resistance of fungi to most drugs has emerged, which has triggered considerable interest in identification of novel antifungal molecules (Viscoli & Castagnola, 1998).The recent past has witnessed the introduction of a few promising second-generation triazoles (voriconazole, ravuconazole and posaconazole) but they are still undergoing clinical trials. These molecules are reported to show broad spectrum in vitro activity against clinical isolates of pathogenic fungal species (Graybill et al., 1998). Studies carried out on voriconazole, ravuconazole and posaconazole using immunocompromised animal models (Sheehan et al., 1999) and the published data from clinical trials have demonstrated improved antifungal efficacy (Walsh et al., 2002). However, the serious problem of cross-resistance may still persist since these molecules have structural similarities with first-generation triazole drugs and use the same pathway for exhibiting antifungal activity. Escherichia coli is a common commen...