Research Projects

Currently, there is no information available on the role of the proteins, which are exactly involved in the control of mycelial aggregation of Streptomyces toxytricini. During submerged fermentation conditions, Streptomyces toxytricini exhibit morphologies between diffused mycelia and pellets as per the culture conditions. It is evident that mycelial morphologies are associated with the production of the desired natural product. Moreover, the pellet morphologies affect the rheology of the medium, heterogeneous mass transfer, and downstream processing. Therefore, regulation of pellet morphology is necessary for industrial processes for natural lipase inhibitor i.e., lipstatin. The analysis and optimization of the fermentation process of Streptomyces have been experimental and mainly centred on the diagnosis of the biophysical framework, biochemical analysis of proteins involved in pellet formation. Limited reports are available on involvement of many proteins (DivIVA, Scy, FilP, SsgA, ParA, Tat, CslA, Afsk, CRP, HyaS, and Mat complex etc) with apical growth, formation of septa, branching in growing hyphae in Streptomyces coelicolor, S. lividans, and S. griseus. No attempt was made for identification and characterisation of genes involve in mycelial aggregation of S. toxytricini. Reverse engineering would be feasible approach in the genomic era to investigate the novel genes involved in pellet formation. On the basis of previous study, it will be evident that there is possibility to regulate pellet morphology by knock-in, knock-out and/or knock down. We have done draft genome sequencing of S. toxytricini as well as isolated extracellular and intercellular proteins further protein sequencing was also performed, which showed 40 proteins were found interacting with each other under Streptomyces dataset. Bioinformatics analysis showed rpsB and dnaK were found to be interacting with maximum number of proteins and possibly regulating the mycelial network. Molecular level analysis is yet to be learned about genes which control liquid culture morphogenesis. Interlinked morphology of mycelial aggregation is the key issue in the commercial application of S. toxytricini. We are working on the S. toxytricini (detail images can be seen in Other Technical Details) a pellet images of S. toxytricini (SEM and simple pictures on glass slide) in liquid culture are showing the more branching in mycelium will increase dense pellet. Preliminary results are very interesting when we isolated proteins having less than 20 kDa after sequencing of the proteins bioinformatics analysis was performed and found that gene sequences are available in draft genome of S. toxytricini (sequenced by my group). Corresponding gene could be engineered for understanding the role in mycelial aggregation. The results obtained from modified S. toxytricini will be validated in bioreactor and kinetic modelling be also be done, which will lead to confirmation.