Biochemical markers assisted screening of Fusarium wilt resistant Musa paradisiaca (L.) cv. Puttabale micropropagated clones.

An efficient protocol was standardized for screening of panama wilt resistant Musa paradisiaca cv. Puttabale clones, an endemic cultivar of Karnataka, India. The synergistic effect of 6-benzyleaminopurine (2 to 6 mg/L) and thidiazuron (0.1 to 0.5 mg/L) on MS medium provoked multiple shoot induction from the excised meristem. An average of 30.10 ± 5.95 shoots was produced per propagule at 4 mg/L 6-benzyleaminopurine and 0.3 mg/L thidiazuron concentrations. Elongation of shoots observed on 5 mg/L BAP augmented medium with a mean length of 8.38 ± 0.30 shoots per propagule. For screening of disease resistant clones, multiple shoot buds were mutated with 0.4% ethyl-methane-sulfonate and cultured on MS medium supplemented with Fusarium oxysporum f. sp. cubense (FOC) culture filtrate (5–15%). Two month old co-cultivated secondary hardened plants were used for screening of disease resistance against FOC by the determination of biochemical markers such as total phenol, phenylalanine ammonia lyase, oxidative enzymes like peroxidase, polyphenol oxidase, catalase and PR-proteins like chitinase, β-1-3 glucanase activities. The mutated clones of M. paradisiaca cv. Puttabale cultured on FOC culture filtrate showed significant increase in the levels of biochemical markers as an indicative of acquiring disease resistant characteristics to FOC wilt.

Preparation and clinical application of a novel monoclonal antibody against Mycobacterium tuberculosis culture filtrate protein 10 / 中华临床感染病杂志

Objective To prepare a novel monoclonal antibody (mAb) that specifically against Mycobacterium tuberculosis culture filtrate protein 10 (CFP-10).Methods The BALB/c mice were immunized by a peptide with 14 amino acids (aa residues 53 to 66) of CFP-10,and then the splenocytes of mice were fused with myeloma cell line SP2/0.The resultant fused cells were subjected to screening culture,enzyme linked immunosorbent assay (ELISA) assay and subcloning by limited dilution to establish hybridoma cell lines of stable secreting anti-the peptide of CFP-10 antibody.The antibody was purified,and its isotypes were analyzed.Then,the antibody was further evaluated by Western blotting,immunoprecipitation and ELISA in 38 culture supernatant samples of Mycobacterium tuberculosis,20 culture supernatant samples of non-Mycobacterium tuberculosis,32 samples of tuberculous pleural effusion,24 samples of non-tuberculous pleural effusion,and 20 serum samples from healthy controls.Results The isotype of the mAb against the specific peptide of CFP-10 was an IgG1 with κ chain,and it was applicable for Western blotting and immunoprecipitation analysis.ELISA quantitative test showed that the sensitivity and specificity for diagnosis of Mycobacterium tuberculosis were 78.6％ (55/70) and 92.2％ (59/64),respectively.Conclusion The mAb generated against the specific peptide of CFP-10 is high in sensitivity and specificity,and it might be used in the early diagnosis of tuberculosis.

Biological Control of Aphid Using Fungal Culture and Culture Filtrates of Beauveria bassiana

Aphids are one of the most destructive pests in crop production such as pepper, cucumber, and eggplants. The importance of entomopathogenic fungi as alternative pest control agents is increasing. Conidia of entomopathogenic fungi are influenced by environmental conditions, such as temperature and relative humidity, and cause slow and fluctuating mortality. These factors have prevented wider application and use of biocontrol agents. For investigation of means of mitigation of such problems, we conducted bioassays with 47 fungal culture filtrates in order to evaluate the potential of secondary metabolites produced by entomopathogenic fungi for use in aphid control. Among 47 culture filtrates cultured potato dextrose broth, filtrate of Beauveria bassiana Bb08 showed the highest mortality (78%) against green peach aphid three days after treatments. Filtrate of Bb08 cultured in Adamek's medium showed higher toxicity as 100% to third instar nymphs of the aphid compared with seven other filtrates cultured in different broths amended with colloidal chitin or oil. The culture filtrates and fungal cultures from media amended with colloidal chitin or oil had lower control efficacies than filtrates without these additives in three different media. These results indicate that the fungal culture fluid or culture filtrate of B. bassiana Bb08 cultured in Adamek's medium has potential for development as a mycopesticide for aphid control.

T-cell recognition of iron-regulated culture filtrate proteins of Mycobacterium tuberculosis in tuberculosis patients and endemic normal controls.

Background: Culture filtrate proteins (CFPs) of Mycobacterium tuberculosis are potential vaccine candidates. Objective: The aim was to study the influence of iron levels on CFPs and assess the immuno-protective potential of defined antigenic fractions from high (8 μg Fe/mL) and low iron (0.02 μg Fe / mL) cultures of M. tuberculosis. Materials and Methods: The CFPs of M. tuberculosis from high (CFP-high) and low (CFP-low) iron conditions were first compared to identify iron-regulated proteins and then fractionated to obtain ten antigen pools (CF-Ags H1- H5 and L1-L5) that were used to assess the immune response of TB patients and normal healthy controls. Results: Iron limitation resulted in the up-regulation of two novel iron-regulated low-molecular-weight proteins Irp-1 (in CF-Ag L4) and Irp-2 (in CF-Ag L5) and repression of two ESAT proteins (identified with monoclonal antibody HYB 76.8). The median stimulation indices (SIs) against most of the CF-Ags were high in pulmonary TB patients. The CF-Ags L1 and L2 showed statistically significant SI (P values of 0.0027 and 0.0029 respectively); the % case recognition was high with these antigens as well as with L4 ( P = 0.0275). IFN-γ in response to these CF-Ags was significantly high in the endemic normals; maximal expression was seen with CF-Ag L5 (median value of 233 pg mL -1 ) that was higher than the corresponding H5 (140 pg mL -1 ) and H3 and L3 (205 and 206 pg mL -1 respectively). Conclusions: CF-Ags L5, H3 and L3 showed immuno-protective potential in this geographical location.

Whole cell & culture filtrate proteins from prevalent genotypes of Mycobacterium tuberculosis provoke better antibody & T cell response than laboratory strain H37Rv.

Background & objectives: The immune responses to different antigens of Mycobacterium tuberculosis H37Rv vary from patient to patient with tuberculosis (TB). Therefore, significant difference might be documented between the H37Rv with long histories of passages and recent clinical isolates of M. tuberculosis. In the present study, immune response of TB patients and healthy controls against 39 clinical M. tuberculosis isolates was correlated with laboratory strain H37Rv. Methods: The antibody response was studied coating whole cell extracts and culture filtrate proteins of M. tuberculosis isolates and laboratory strain H37Rv by enzyme linked immunosorbent assay (ELISA). Lymphoproliferation was studied by incorporation of tritiated thymidine and cytokines (IFN-γ and IL-4) by using commercially available kits. Results: Sero-reactivity to whole cell extract (WCE) of 11 clinical isolates was higher with pooled serum and individual's serum from tuberculosis patients showed significant reactivity (P<0.05) to ten of these isolates using ELISA. Of the WCE of 39 clinical isolates, 10 were found to be potent inducer of lymphoproliferation as well as cytokine secretion (P<0.05) in peripheral blood mononuclear cells from PPD+ healthy controls. Six culture filtrate proteins (CFPs) from these selected clinical isolates were also better inducers of antibody and T-cell response. Interpretation & conclusion: Overall, our results revealed that the clinical isolates belonging to prevalent genotypes; CAS1_Del (ST-26), East African-Indian (ST-11) and Beijing family (ST-1) induced better antibody and T cell responses compared to H37Rv laboratory strain. Further studies need to be done to purify and identify the dominant protein (s) using whole cell extract and culture filtrates from these immunologically relevant clinical M. tuberculosis isolates, which will be worthwhile to find out pathogenic factors, potential diagnostic markers and protective molecules for tuberculosis.

Production and extraction of phytotoxins from Colletotrichum dematium FGCC# 20 effective against Parthenium hysterophorus L

The aim of this work was to study the herbicidal potential of Cell free culture filtrate of Colletotrichum dematium FGCC#20 against Parthenium by employing different bioassays i.e. shoot-cut, seedling, detached leaf and seed germination. On solvent extraction of the Cell free culture filtrate, Ethyl acetate extracted fraction showed the presence of phytotoxic moiety.

A simple and rapid method of sample preparation from culture filtrate of M. tuberculosis for two-dimensional gel electrophoresis

Sample preparation for Two-dimensional gel electrophoresis (2DE) is tedious and not sufficient to provide a comparative profile of secreted proteins for various strains of M. tuberculosis. High lipid content in mycobacteria limits the use of common methods as it can hinder the 2DE run. This study highlights the significance of SDS-TCA procedure over common used methods for the preparation of sample from culture filtrate as well as other proteinaceous fluids.

Cytokine Profiles of Macrophages by Mycobacterium abscessus Conditional Morphotype Variants and Comparison of Their Extracellular-Protein Expressions

Mycobacterium abscessus has been identified as an emerging pulmonary pathogen in humans. Previously, it was documented that a spontaneously formed rough variant of M. abscessus causes persistent and invasive infection in mice, while a smooth isogenic variant does not. However, little is known for immune responses elicited by M. abscessus variants artificially induced by culture conditions and their culture filtrate antigens. Thus, morphological variants of M. abscessus type strain (ATCC19977T) were generated by an acidic and low oxygen culture conditions. Overall comparison between the variant and its original smooth strain showed that the rough variant was less virulent than original smooth strain in murine bone-marrow derived macrophage. To understand the basis for the difference, the protein expression pattern in the culture filtrates of each strain was analyzed by 1-dimensional electrophoresis. Generally, the protein expressions were more influenced by pH conditions than oxygen pressures. Interestingly, several proteins, mainly lower than 30 kDa molecular weight, were uniquely expressed in normal culture conditions. In contrast, several high molecular weight proteins (>55 kDa) were induced by acidic and low oxygen culture conditions. These findings not only provide new insights of association between morphological change and the virulence, but may also be useful in the design of immunological diagnosis and vaccines for M. abscessus infection.

Diagnostic Significance of the Serologic Test Using Antigen of Mycobacterium Tuberculosis for Antibody Detection by ELISA / 결핵

BACKGROUND: Diagnosis by direct microscopy and/or by culture of the Mycobacterium tuberculosis from body fluids or biopsy specimens is "Gold standard". However, the sensitivity of direct microscopy after Ziehl-Neelsen staining is relatively low and culture of mycobacteria is time consuming. Detection of mycobacterial DNA in clinical samples by the polymerase chain reaction is highly sensitive but laborious and expensive. Therefore, rapid, sensitive and readily applicable new tests need to be developed. So we had evaluated the clinical significance of serologic detection of antibody to 38 kDa antigen, which is known as the most specific to the M. tuberculosis complex, and culture filtrate antigen by ELISA in sputum AFB smear negative patients. METHOD: In this study, culture tests for acid fast bacilli with sputa or bronchial washing fluids of 183 consecutive patients who were negative of sputum AFB smear were performed. Simultaneously serum antibodies to 38 kDa antigen and unheated culture filtrate of M. tuberculosis were detected by an ELISA method. RESULTS: The optical densities of ELISA test with 38 kDa and culture filtrate antigen were significantly higher in active pulmonary tuberculosis cases than in non tuberculous pulmonary diseases (pO.05). In the smear-negative active pulmonary tuberculosis patients, the sensitivity of the ELISA using 38 kDa antigen and culture filtrate was 20.0% and 31.4%, respectively. The specificity was 95.3% and 93.9%, respectively. CONCLUSION: In active pulmonary tuberculosis but smear negative, the serologic detection of antibody to 38 kDa antigen and culture filtrate by ELISA cannot substitute traditional diagnostic tests and does not have clinically significant role to differenciate the patient with active pulmonary tuberculosis from other with non-tuberculous pulmonary diseases.