TWAS Funded Research Projects
Project Title: To explore novel soil Streptomyces in Nepal in pursuit of potential antibiotics using Biochemical and Molecular Methods
Project Introduction: Streptomycetes are masters of secondary metabolism. Besides antibiotics, diverse natural products produced by Streptomyces possess a variety of pharmacological activities including antitumor, antifungal, antiparasitic and immunosuppressant activities, and are used in clinical and veterinary medicine. Actinomycetes had yielded ~3,000 known antibiotics, 90% of those from Streptomyces. The worldwide emergence of multidrug resistant pathogens has become a major therapeutic problem. Moreover, there has been an alarming increase in the incidence of new and re-emerging infectious diseases. Thus, in light of the evidence of rapid global spread of resistant pathogens and new infectious diseases, the need of finding new therapeutic agents against these diseases is of paramount importance.
The distribution of Streptomyces, well known for their secondary metabolite production, is believed to be influenced by soil geochemistry and local microbial community composition. Nepal has large variation in soil type and its contents due to large geographic variation. As a consequence, abundance and the distribution of Streptomyces are also variable with diverse morphology, physiology, and biochemical activities. However, awareness of these facts and studies on enumeration, isolation and screening of actinomycetes for potential bio-activity has so far remained limited in Nepal.This study aims to investigate Streptomyces complexes in various soil biotopes of Nepal and to explore the drugs/antibiotics production potentials of these indigenous Streptomyces.
Project Title: Investigation of pathogenic bacteria and their biofilm composition in oral cavity of Nepalese population from different geographic location and analysis of its impacts on distribution, genetic variation, and pathogenic potential
Project Introduction: Poor oral cavity hygiene is the major cause of the many dental related health issues. In order to develop efficient oral cavity cleaning products, there should be enough scientific information about the oral microbial diversity in biofilm and its chemical composition. Such scientific data is not available here for Nepalese population. Due to various geographic variations and multiple ethnic populations with multiple cultures and living customs, different oral microbial composition must be obtained. In the present research project, we will investigate oral microbial diversity in Nepalese population from various altitudinal locations, ethnic groups, and various age groups. In addition, genetic variation of microbial species with respect to geographical location and their biochemical and physiological variation will be investigated. We will also investigate chemical secretion of microbial flora in the oral biofilm by using LC-MS and GC-MS analysis. Similarly, microbial enzyme production will also be explored. The co-relation between the oral disease and microbial diversity along with chemical composition of bio-film and extracellular enzymes secreted by microbial species will be investigated. The overall scientific data will pave the way to describe the distribution, pathogenic potential, physiology and genetic variation of pathogenic oral micro-organisms in Nepalese communities. Such information would pave the way to design and produce proper and effective oral cleaning products commercially.
Project Title: Synthesis and characterization of non-viral vectors for efficient gene delivery.
Project Introduction: Viral vectors are usually used for gene therapy to deliver genes into cells. However, the delivery of genes by virus raises safety concerns. As an alternative, synthetic polymer-based (non-viral) vectors have emerged as a promising gene vehicle because cationic polymers have ability to make complexation with gene to form polymeric nanoparticles for gene transfection. Importantly, a successful gene delivery requires to overcome several limitations, such as cytotoxicity, cellular uptake and endosomal escape. Although each barrier represents a critical step in determining the final efficiency of gene delivery, the release of DNA from endosomes, that is, endosomal escape prior to their degradation in lysosomes, appears to be a major bottleneck. It is now well-documented that polyethylenimine (PEI) induces endosomal escape due to its buffering capacity. Although the high density of positive charges of PEI is rewarding to polymer for buffering capacity, it contributes to high cytotoxicity. Hence, much attention has been given to design polymeric vectors aiming for efficient transfection with low cytotoxicity. Although the scope of non-viral gene delivery is promising, no report has been published from any institute or University till date from Nepal. This study aims to synthesize various gene delivery vectors, and test them for possible use in gene transfection.
Project Title: Utilizing cationic peptides for the development of novel antibacterial hydrogels for addressing bacterial infections in an environment of increasing bacterial resistance to existing antibiotics.
Hydrogels are becoming popular in the field of biomedical research due its applicability in many functional applications. While conventional hydrogels use synthetic polymers, hydrogels formed by molecules that self-assemble via noncovalent forces are gaining popularity due to enhanced biocompatibility. Therefore Low Molecular Weight (LMW) based hydrogelators are an attractive alternative to the synthetic polymer gelators due to its reduced cost and synthetic customizability. My previous work has shown that cationic peptides such as (FKFK)2 and Fmoc-Phe derivatives have the ability to spontaneously self-assemble to form rigid hydrogels that satisfies most of the criteria needed for cell culture applications. It has also been reported that cationic polymers and peptides have the ability to display efficient antibacterial activities. Hence, we can hypothesize that the polymeric fibrils of these cationic molecules can be also utilized to form hydrogels that can support mammalian cells while displaying antibacterial properties. Such gels are highly desirable because these gels can be potentially applied against bacterial infectivity in countries such as Nepal where bacterial infections impose a great threat in the general public health. For our research, we plan to utilize these gels to probe its ability to sustain mammalian cells while inhibiting bacterial cells by using spectrophotometer, fluorescence/confocal microscope to quantify live/dead assay of the cells within the gel.