Expression and purification of the transcription factor StMsn2 from Setosphaeria turcica in Escherichia coli

Background: In Saccharomyces cerevisiae, Msn2, which acts as a key transcription factor downstream the MAPKHOG cascade pathway, also regulates the expression of genes related to stress responses. However, little is known about the regulation mechanisms of the transcription factor in Setosphaeria turcica. Results: In this study, a zinc finger DNA-binding protein, designated as StMSN2, was cloned from S. turcica. Sequencing results showed that StMSN2 had a 1752 bp open reading frame (ORF), which was interrupted by an intron (135 bp) and encoded a putative 538-amino acid protein. Phylogenetic analysis further revealed that StMsn2 was more closely related to Msn2 of Aspergillus parasiticus. StMSN2 was cloned into the pET-28a vector with His (Histidine) tags and induced with 1 mM IPTG (isopropyl-ß-D-thiogalactoside) at 37°C. The recombinant His-tagged StMsn2 was purified, and a band of size approximately 58.8 kDa was obtained. The high specificity of the polyclonal antibody Msn2-2 was detected with the StMsn2 protein from S. turcica and prokaryotic expression system, respectively. Conclusions: A new gene, named StMSN2, with 1617 bp ORF was cloned from S. turcica and characterized using bioinformatics methods. StMsn2 was expressed and purified in a prokaryotic system. A polyclonal antibody, named Msn2-2, against StMsn2 with high specificity was identified.

Party for killing: the social behaviors in Cryptococcus neoformans / 生物工程学报

Fungal pathogens represent an important group of human pathogenic microbes that lead to an unacceptably severe global burden especially due to exceptionally high mortality. For many fungal pathogens, they are widespread saprophytes and human host is not the exclusive niche for their proliferation. Their exceptional capability to survive and thrive within infected host likely stems from their sophisticated strategies in adaptation to diverse biotic and abiotic stressors from natural niches or predators. Among these 'environmental pathogens', Cryptococcus neoformans as a model organism claims the lives of more than half a million annually. Some recent studies indicate that cryptococcal survival both inside and outside of hosts can be coordinated by a combination of social behaviors. In this review, we describe and discuss the social behaviors employed by C. neoformans and address their significant impact on biofilm formation, sexual reproduction and pathogenicity.

In Vitro Antagonism and Evaluation of Chitinase Activity of Bacteria–Bacillus Circulans Against Pathogenic Fungi in Vigna Unguiculata.

Scientists of agriculture and plant pathology are on the lookout for potential biological control agents to control the plant pathogenic organisms in order to avoid soil contamination. Rhizospheric bacteria are excellent agents to control soil-borne plant pathogens. In this study an attempt has been made to evaluate the antagonistic activity of a bacterial strain Bacillus circulans against Curvularia lunata, Alternaria alternata and Cladosporium sp., which are important seed and soil borne pathogens distributed throughout the world. These infections cause grain mold and leaf spot diseases, resulting in significant economic loss to the crops. A soil bacterium Bacillus circulans isolated from the rhizospheric soil of Vigna unguiculata, showed high antagonistic activity against Curvularia lunata, Alternaria alternata and Cladosporium sp. on dual plate assay. Bacillus circulans showed a distinct inhibition zone in the dual plate assay and also produced a clear inhibition zone in chitin amended agar medium containing 0.5% colloidal chitin, indicating that it secretes chitinase.

Preliminary Study on Some Actinomycetes and Evaluation of Their Potential Antagonism against Fungal Pathogens.

Aims: Control of microbial pathogens by using antagonistic microorganisms is a promising alternative to chemical fungicides. The objective of the present study was to isolate and characterize soil actinomycetes and to their inhibitory activity against some fungal plant pathogens. Place and Duration of Study: National Park “El Chico”, Hidalgo State, and Laboratory of the Southeast Unit of CIATEJ, Yucatán, México, between June 2010 and May 2011. Methodology: Actinomycete species were isolated from six composite soil samples using microbiological standard procedures. All isolates were phenotypically characterized. Antagonistic isolates were selected according to the inhibitory growing of Fusarium sp. and Candida albicans. Afterwards, a new evaluation for the isolates selected was done against Helminthosporium sp., Curvularia sp., and Aspergillus niger. Actinomycetes were identified performing an analysis of the 16S rDNA gene sequence. Results: 164 actinomycete strains were characterized by morphological and biochemical features. Six of them, inhibited the growth of Fusarium sp. and C. albicans from 5 to 10 mm distance in between the actinomycete´s colony growth border of fungal or yeast. A growing reduction from 50 to 83 % in the in vitro antagonism assays was observed for Helminthosporium sp., Curvularia sp., and Aspergillus niger. Results in disc diffusion assays suggested an inhibitory growing capacity of CACIA-1.46HGO for P. capsici, this behavior could be due to the production of diffusible compounds related to secondary metabolism, hydrolytic enzymes, or both of them. Four antagonistic isolates were identified into Streptomyces genus and one as Microbacterium sp. through 16S rDNA gene sequence. Conclusion: Actinomycetes could be potentially a control tool to prevent several fungal commercial plants diseases. However, in situ isolate evaluations are suggested to be investigated.

Analysis of Chemical Components and Antifungal Activity of Extraction from Conidia of Trichoderma viride LTR-2 / 微生物学通报

To study the chemical components and the antifungal activity of extraction from conidia of Trichoderma viride LTR-2.The extraction were obtained by distilling with Methylene dichloride from conidia of Trichoderma viride LTR-2 cultured on wheat bran solid matrix.Antifungal activity were determined by mycelium growth method.The chemical components of the extraction were analysed by GC-MS,the relative components in the extraction were determined by area normalization.The extraction not only have broad-spectrum control,showed antibiosis against eleven different plant fungal pathogens in PDA dish,such as Rhizoctonia solani,Alternaria brassica,Verticillium dahliae,Macrophoma kawatsukai,Fusarium moniliforme,Botrytis cinerea,Rhizoctonia cerealis,Fusarium oxysporum f.sp.vasinfectum,Bipolaris sorokinana,Fusarium graminearum,Alternaria.mali,but also have high inhibitory effect,and had 89.3% suppressive rate to Rhizoctonia cerealis.About sixty components were separated and identified by GC-MS,majority components were Hydrocarbon,the number of the Hydrocarbon were fourty-three kinds.Ergosterol was the major chemical components of the extract,and has 41.90% content.Other components comprised:Ketone,Organic acid,Alcohol,Ene,et al.Conclusion:The extraction from conidia of Trichoderma viride LTR-2 have antifungal activity.The extration comprised 2H-Pyran-2-one,5,6-dihydro-6-pentyl,it has 2.35% content.reference others literature,2H-Pyran-2-one,5,6-dihydro-6-pentyl may be the suppressive component of the extration.