Optimization of lignin peroxidase production and stability by <Emphasis Type="Italic">Phanerochaete chrysosporium</Emphasis> using sewage-treatment-plant sludge as substrate in a stirred-tank bioreactor

A laboratory-scale study was carried out to produce lignin peroxidase (ligninase) by white rot fungus (Phanerochaete chrysosporium) using sewage-treatment-plant (STP) sludge as the major substrate. The optimization was done using full-factorial design (FFD) with agitation and aeration as the two parameters. Nine experiments indicated by the FFD were fermented in a stirred-tank bioreactor for 3 days. A second-order quadratic model was developed using the regression analysis of the experimental results with the linear, quadratic, and interaction effects of the parameters. Analysis of variance (ANOVA) showed a high coefficient of determination (R ²) value of 0.972, thus indicating a satisfactory fit of the quadratic model with the experimental data. Using statistical analysis, the optimum aeration and agitation rates were determined to be 2.0 vvm and 200 rpm, respectively, with a maximum activity of 225 U l⁻¹ in the first 3 days of fermentation. The validation experiment showed the maximum activity of lignin peroxidase was 744 U l⁻¹ after 5 days of fermentation. The results for the tests of the stability of lignin peroxidase showed that the activity was more than 80% of the maximum for the first 12 h of incubation at an optimum pH of 5 and temperature of 55°C.     

Anti-CD37 targeted immunotherapy of B-Cell malignancies

CD37 is a member of tetra-spanning superfamily (characterized by their four transmembrane domains). It is one of the specific proteins for normal and malignant mature B cells. Anti CD37 monoclonal antibodies are reported to improve the overall survival in CLL. These therapeutics will increase the efficacy and reduce the toxicity in patients with both newly diagnosed and relapsed and refractory disease. Recent clinical trials have shown promising outcomes for these agents, administered both as monotherapy and in combination with standard chemotherapeutics. Long-term follow-up of combination regimens has even raised the question of whether the patients with CLL could be treated with intensive chemo-immunotherapy. In the present study, CD37 is introduced as an appealing target to treat B cell malignancies. The anti-CD37 antibodies as one of the most successful therapeutics against CD37 are introduced and the clinical outcomes of their exploitation are explained.     

Siderophore mediated iron(III) uptake in Gliocladium virens. 1. Properties of cis-fusarinine, trans-fusarinine, dimerum acid, and their ferric complexes

Gliocladium virens (ATCC 24290) produces two monohydroxamates (cis- and trans-fusarinine) and a dihydroxamate (dimerum acid) as the major siderophores in the culture filtrate. This fungus also produces minor quantities of three trihydroxamates (the deferri forms of ferricrocin, coprogen B, and coprogen). Structural features of the free ligands and the metal complexed forms of cis-fusarinine (cF), trans-fusarinine (tF), and dimerum acid (DA) have been investigated using electronic (visible), circular dichroism (CD), and NMR spectroscopy. In aqueous solution, in the pH range of 6.5-8.0, all of the ferric complexes of cF (and tF) exist as 3:1 chelates. Fe(cF)3 [or Fe(tF)3] forms both lambda and delta coordination isomers, but the former in a slight excess. DA forms a 3:2 ferric complex in the pH range of 5.0-8.0. Iron coordination in Fe2(DA)3 is predominantly delta. DA ligands in Ga2(DA)3 exist as two different conformers at a ratio of 2:1. In mixed solution cF, tF, and DA form a large number of homogeneous and heterogeneous Fe(III) chelates.     

Increased rates of sister chromatid exchanges induced by the herbicide 2,4-D

The potential for genetic damage from widely used hormonic herbicides, such as 2,4-dichlorophenoxyacetic acid (2,4-D), continues to be of serious concern. The mutagenic effect as reflected by the rates of sister chromatid exchanges (SCE) was determined in cultured human lymphocytes. Data were based on the analysis of 50 cells for the control and each of the three treatments. A 50 micrograms/ml dosage caused a highly significant increase in SCE. Dosages of 100 and 250 micrograms/ml elevated the rate of SCE, but not significantly. Since 2,4-D biodegrades rapidly in soil and water, its continued use is not in serious question until safer compounds are available. However, the results of this study suggest that the danger of genetic damage from direct exposure to commercial samples of 2,4-D should not be ignored.     

<Emphasis Type="Italic">Peristylus sahanii</Emphasis>, a new species of Orchidaceae from India

Peristylus sahanii (Orchidaceae), a new species from Jharkhand state (Chotanagpur plateau), India is described and illustrated.     

Genetic diversity in a collection of old and new bread wheat cultivars from Iran as revealed by simple sequence repeat-based analysis

Genetic diversity in a collection of 70 bread wheat ( Triticum aestivum ) genotypes was studied using 73 microsatellite [simple sequence repeat (SSR)] loci evenly spaced on wheat chromosomes. A total of 592 alleles with an average of 8.53 allele/locus were detected, of which 185 (31.25%) occurred only in a specific group of genotypes. A set of SSR markers consisted of 22 loci with polymorphic information content values of 0.80 or higher were selected for rapid fingerprinting of many genotypes. Average of gene diversity was 0.74 ± 0.017, and significant difference between observed and maximum theoretical values of gene diversity in the analysed SSR loci was obtained using a paired t -test. Genetic distance-based clustering methods including unweighted pair group method with arithmetic average and neighbour joining (NJ) were used for grouping of genotypes. The resulted dendrogram based on NJ and number of differences coefficient hinted of the existence of three groups. This grouping was in agreement with the pedigree information and confirmed by high within-group bootstrap value. A comparatively higher genetic diversity in the studied wheat collection as revealed by presence of high allelic diversity and large number of specific alleles could be utilised in development of new cultivars with desired characteristics.