Statistical optimization of medium components to increase the manganese peroxidase productivity by Phanerochaete chrysosporium NCIM 1197

The production of manganese peroxidase (MnP) by the white-rot fungus Phanerochaete chrysosporium NCIM 1197 was investigated by the screening and optimization of the media constituents and physiological factors. MnP production by the fungus was used as the response to screen the media constituents with statistically valid Plackett-Burman (P-B) design. Response surface methodology (RSM) was applied to optimize the level of screened media constituents. Amongst the media constituents screened, glucose, maltose, ammonium chloride, and urea were selected as the most important for MnP enhancement. A five-level Central Composite Design (CCD) was used in optimizing the important media constituents for maximizing the MnP production. The optimal medium composition for maximum MnP production was 13.88 mM of glucose, 13.88 mM of maltose, 0.02 mM of ammonium chloride, and 0.02 mM of urea. The final experiment was conducted to validate the model, which was shown to produce 70.20 U/mL of MnP with a predicted value of 66.49 U/mL on the 8^th day of incubation.     

Cardiolipin-mediated PPARγ S112 phosphorylation impairs IL-10 production and inflammation resolution during bacterial pneumonia

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Cloning, over-expression and biochemical characterization of the single-stranded DNA binding protein from Mycobacterium tuberculosis.

The single-stranded DNA binding protein (SSB) plays an important role in DNA replication, repair and recombination. To study the biochemical properties of SSB from Mycobacterium tuberculosis (MtuSSB), we have used the recently published genome sequence to clone the ssb open reading frame by PCR and have developed an overexpression system. Sequence comparison reveals that the MtuSSB lacks many of the highly conserved amino acids crucial for the Escherichia coli SSB (EcoSSB) structure-function relationship. A highly conserved His55, important for homotetramerization of EcoSSB is represented by a leucine in MtuSSB. Similarly, Trp40, Trp54 and Trp88 of EcoSSB required for stabilizing SSB-DNA complexes are represented by Ile40, Phe54 and Phe88 in MtuSSB. In addition, a group of positively charged amino acids oriented towards the DNA binding cleft in EcoSSB contains several nonconserved changes in MtuSSB. We show that in spite of these changes in the primary sequence MtuSSB is similar to EcoSSB in its biochemical properties. It exists as a tetramer, it has the same minimal size requirement for its efficient binding to DNA and its binding affinity towards DNA oligonucleotides is indistinguishable from that of EcoSSB. Furthermore, MtuSSB interacts with DNA in at least two distinct modes corresponding to the SSB35 and SSB56/65 modes of EcoSSB interaction with DNA. However, MtuSSB does not form heterotetramers with EcoSSB. MtuSSB therefore presents us with an interesting system with which to investigate further the role of the conserved amino acids in the biological properties of SSBs.     

Molecular Docking-Based Identification of Potential Natural Neuroprotective Molecules for Parkinson's Disease

Background: Parkinson's disease (PD) is a common progressive neurodegenerative and the prevailing treatments are ineffective in the early stages of the disease. Therefore, other strategies must be devised to halt the steady decrease of dopaminergic neurons in the brain. In Parkinson's disease, a dysregulated ACE/Ang II/AT1R axis in the brain causes free radical damage, apoptosis, and neuronal destruction. Current PD treatments only alleviate symptoms and do not reverse the degradation mechanism of dopaminergic neurons. As a result, it is critical to discover alternate, dependable medicines for the treatment of Parkinson's disease. Method : In the present study, homology modelling of MAS receptor, in silico docking and molecular dynamic studies (MDS) were employed to determine the efficacy of flavonoids as MASR activators. Result : The flavonoids Pterosupin and Amentoflavone exhibited best binding and therefore, the stability of these complexes were evaluated with MDS studies. The Pterosupin-MASR complex demonstrated better stability, stronger interactions and minimal fluctuation than the Amentoflavone-MASR complex. Conclusion : The data from the present study indicated that the flavonoid Pterosupin possesses better binding, favourable pharmacokinetic properties and stability. However, subsequent in vitro and in vivo assessments are necessary to validate its efficacy.     

Retrospective assessment of clonal origin of cell lines

Cell lines used for the manufacture of recombinant proteins are expected to arise from a single cell as a control strategy to limit variability and ensure consistent protein production. Health authorities require a minimum of two rounds of limiting dilution cloning or its equivalent to meet the requirement of single cell origin. However, many legacy cell lines may not have been generated with process meeting this criteria potentially impeding the path to commercialization. A general monoclonality assessment strategy was developed based on using the site of plasmid integration for a cell's identity. By comparing the identities of subclones from a master cell bank (MCB) to each other and that of the MCB, a probability of monoclonality was established. Two technologies were used for cell identity, Southern blot and a PCR assay based on plasmid-genome junction sequences identified by splinkerette PCR. Southern blot analysis revealed that subclones may have banding patterns that differ from each other and yet indicate monoclonal origin. Splinkerette PCR identifies cellular sequence flanking the point(s) of plasmid integration. The two assays together provide complimentary data for cell identity that enables proper monoclonality assessment and establishes that the three legacy cell lines investigated are all of clonal origin.     

The directional absorption properties of rhodopsin and its photoproducts

The experimental data on the absorption of a plane polarised light by a solution of cattle rhodopsin at −196‡ C have been theoretically analysed to model the directional absorption properties of rhodopsin and its photoproducts. It is seen that these molecules behave like planar absorbers having a ratio of about 100∶7 between the extinction coefficients along the long axis and perpendicular to it. Using this result and the experimental observations on absorption and dichroism in the retina in situ, a model for the configuration of chromophores in the disc membranes has been derived. In this model the plane of the chromophore is perpendicular to that of the disc and the long axis of the chromophore makes an angle of 6.6‡ with the plane of the disc. The solution of the problem depends on the assumption that the absorption axes are the same for the rhodopsin, prelumirhodopsin and isorhodopsin. Work partially supported by Department of Science and Technology (India)     

Future directions in the study of induced plant responses to herbivory

This paper reviews current progress and makes recommendations for future studies of induced plant responses to herbivory in three research areas: the role of induction in structuring herbivore communities, costs associated with the expression of induced responses, and theory and data on the macro‐evolution of induced responses. It is argued that although mechanistic approaches will be important for progress, it is also critical to maintain a holistic approach, including a consideration of field environments, multi‐species interactions, and patterns over ecological and evolutionary time.