We at Molecular Microbiology & Human Diseases intend to find answers to simple but significant questions on human biology and how the human body cope with diseases, especially microorganisms. The research group was initially focused on three main areas: cyanobacteria, pulmonary diseases, and on human gene expression analysis. Currently the focused areas are pulmonary diseases, zoonotic diseases and research on cyanobacteria. Furthermore, the group has studied on human gene expression analysis on CKDu as well as on environmental microbiome.
Study of microbiome is the study of microorganisms in a particular environment. Microorganisms live in our surroundings as well as in and on our body. Findings of human microbiome are fascinating and we try to identify human lung microbiome and its effect on respiratory diseases. This provides an insight to the microbial population associated with the specific diseases and may eventually help to develop new methods for disease diagnosis and treatment.
Most of the causative agents for diseases enter to human body through respiratory tract. Thus, ‘microbes inside human lung’ is an interesting topic. These respiratory microbiota could be beneficial, as well as harmful for personal health. Furthermore, microbes may control the severity of a disease condition and different hosts may have different outcome in the same disease depending on their lung microbiota.
This research focuses on lung microbiome of lung cancer and bronchiectasis patients. It is aimed to study the diversity of microbiota inhabit the lungs of the respective patients and what quantities are there and as to whether there is a connection and an effect of the microbiota towards the patients’ condition. Conventional culturing methods, as well as advanced molecular methods like next-generation sequencing techniques are used to achieve the specific objectives in this project.
We have conducted diverse research projects on tuberculosis over the past few years. The mission of the program is to contribute to the national TB control through research initiatives on its epidemiology, drug resistance and anti-tuberculosis activity. Information on the local patterns of drug susceptibility of Mycobacterium tuberculosis is limited and such studies are timely requirements for effective TB control locally. Currently, the team focusses on multi-drug resistant tuberculosis (MDR-TB), the condition at which the TB bacterium becomes resistant to treatment for the two most powerful first line drugs.
During the study, we would determine the prevalence of MDR-TB in the country, detect the mutations responsible for resistance development and study the differential patterns of host immune responses. Outcome of the research project would help in controlling of drug resistant tuberculosis in the country, establish better procedures to improve the patient status, reduce transmission and the overall healthcare cost spent on tuberculosis in Sri Lanka.
Air borne microorganisms lead to many human respiratory diseases. Respiratory diseases are increasing in Sri Lanka due to rapid development and urbanization which can cause a significant burden on the health care system, which would eventually require an increased budget allocation. Although airborne microbes are recognized as an emerging public health problem in developing countries, such as Sri Lanka most of these countries are not capable of evaluating the actual magnitude of the problem due to the lack of adequate data about airborne microorganisms.
Current studies are focused on identification and quantification of the microbial pollutants of the respirable and deposited atmospheric particles in outdoor and indoor environments of the city of Kandy, Sri Lanka using culture based methods, fluorescence microscopy and quantitative real time PCR. The findings of this research will lead to effective mitigation strategies of respiratory diseases.
Chronic kidney disease of unknown etiology (CKDu) is one of the major health problems in Sri Lanka affecting the farming community of the country since the late 1990’s. Finding its root cause and possible solutions are national priorities. The CKDu project focuses on analyzing the blood transcriptome patterns of CKDu patients in order to better understand the disease, identify possible causative factors and suitable biomarkers for the disease.
Analyzing the expression of genes in CKDu patients and healthy population of CKDu endemic areas could lead to better understanding of the molecular mechanisms involved in the disease. Pilot studies in the lab showed oxidative stress which was influenced by the locality of the individuals. The affected molecular pathways are being studied in depth to eventually aid in the identification of disease etiology and biomarkers for early diagnosis. This could further lead to etiology specific treatment protocols and new strategies to address this issue of national importance.
Cyanobacteria are photosynthetic microorganisms which naturally inhabit lakes, streams, ponds, and other surface waters. Cyanobacteria and their cyanotoxins are one of major contaminants in drinking water sources in dry zones of Sri Lanka because the topographic and climatic conditions provide suitable ecological niches for them to flourish in these regions. At the same time, number of water borne health crisis have been reported in these regions where cyanotoxins could be potential causative agents.
Accordingly, one of the current key frontier research areas in environmental science is related to controlling toxin production and ensuring the safety of drinking water. When cyanobacterial cells are under stress, they undergo Programmed Cell Death (PCD) which is known as Apoptosis. Cyanotoxins are released out by them as a stress response. Various environmental stresses induce apoptosis and toxin release by cyanobacteria. This study evaluates the correlation of apoptosis induction and toxin release in cyanobacteria which is likely to be triggered by factors like oxidative stress and high Fluorides in the medium. On the other hand the growth of cyanobacteria also affected by various factors which in turn alters toxin synthesis and release, therefore the correlation between growth (culture age ), apoptosis and toxin release are also being analyzed by molecular, biochemical and analytical methods.
Zoonotic diseases are infections that can be transmitted between species from animals and humans. Different types of pathogens including viruses, bacteria, parasites, and fungi are involved for the transmission of zoonoses. It involves interaction between at least two species – the pathogen and the host with or without vectors. There 1,415 pathogens known to infect humans, of which 61% are zoonotic.
The project on zoonotic diseases consists of a combination of field based epidemiology activities involving animals and humans, laboratory bench work particularly in pathogen identification. We investigate on the effect of host species diversity on disease prevalence using cloacal microbiome of aquatic wild bird species in national parks in Sri Lanka. This study mainly focuses on elucidating the epidemiology of specific zoonotic pathogens, their transmission as well as activities on pathogen discovery in various reservoir species. We are involved in studies to understand the community structure of bird gut microbiome and its potential influences on human health as well as on the other animals as it play a significant role in emerging/re – emerging zoonotic diseases.
Several research projects, including basic research, have been conducted so far at the IFS, which have yielded promising formulations of BFBFs for tea, rice, maize, vegetables, strawberry, potato and floriculture crops. After extensive research conducted in collaboration with the Tea Research Institute of Sri Lanka, Biofilm-T, the BFBF for tea has now been commercialized in the country by Lanka Bio-Fertilizers (Pvt) Ltd. It was distributed to about 10,000 acres of tea cultivation during 2014. This can cut down 50% of chemical fertilizers used in tea cultivation. This fertilizer technology is now being extended to other crops in agriculture and the plantations. It is hoped that this can save billions of rupees in foreign exchange by reducing fertilizer imports to the country reduce pollution and also the environment.
With the aim to establish scientific bases for a healthy human life, we are conducting extensive research in the field of nutritional biochemistry using in vivo and in vitro assays. This project focuses on various aspects of functional and nutritional properties of foods and covers a wide area like bioactivity of food, bioavailability of food, food safety, and functional food product development. Studies are aimed at pinpointing the beneficial properties of naturally available food sources and in the context of selection of these commodities in food processing, agriculture, and medicine.
Research activities of the Natural Product Project have been focused on the chemistry and bioactivity of secondary metabolites from plants, fungi (including endophytic fungi) and edible fruits of Sri Lanka. Another area of research has been the identification of polyphenols found in tea, fruits and edible spices using Liquid Chromatography-Mass Spectrometry (LC-MS). The overall objective of these projects is the identification bioactive extracts and compounds from natural sources, as potential resources for control of human and plant diseases.
The bioactivities of extracts and compounds are assessed using bioassays such as 2,2’-diphenyl-1picrylhydrazyl [DPPH] radical scavenging assay to detect the presence of natural antioxidants; the brine shrimp (Artemia salina) lethality assay to detect cytotoxicity lettuce (Lactuca sativa) seed germination assay to detect the presence of phytotoxic and allelopathic compounds and TLC bioautography method to detect the presence of antifungal compounds.
Naturally occurring enzyme inhibitors are important in the field of drug research and are biochemical tools that have potential utility in the treatment of diseases. These inhibitors interact with enzymes and block their activity towards their corresponding natural substrate. Inhibitors of -amylase, glucosidase, and lipase are drug targets for the treatments of diabetes, obesity, and hyperlipidemia. Enzyme assays to detect the presence of naturally occurring -amylase, -glucosidase and lipase inhibitors respectively, are being used in the recognition of natural sources that may be of importance in the identification of extracts/compounds that can find application in the formulation of health and food-related products. For example, -amylase, -glucosidase and lipase inhibitors are drug targets for the treatment of diabetes, obesity, and hyperlipemia, and may eventually be of use in drug research leading to the development of new therapeutic products. During 2014 the establishment of assays to detect the presence of inhibitors of urease and chymotrypsin enzymes is in progress.
The accidental discovery of the first antibiotic Penicillin from the mold Penicillium notatum led to the age of antibiotics and research on fungal metabolites. Some endophytic fungal strains produce natural products that are either identical or closely related to those produced by the host plant. Taxol, an anti-cancer drug obtained from the Pacific Yew tree Taxus brevifolia, was also produced by the endophytic fungus Taxomyces andreanae from the bark of T. brevifolia. Isolation of endophytic fungal strains from some Sri Lankan fruits (F. indica, Musa sp., seeds of Pouteria campechiana) and leaves of allelopathic plants has resulted in the isolation of some unusual bioactive metabolites. Compounds isolated from the leaves of Aspergillus niger included polyketide naphthopyrones rubrofurarin, foncesin, aurosperone, fonsecinone A and also ergosterol. Studies on metabolites produced by the Ambrosia fungus Monacrosporium ambrosium, an ectosymbiotic fungus of the Shothole borer beetle (Xyleborus fornicatus) of tea, are in progress.
The Plant and Environmental Sciences group is conducting research related to the plant sciences and the environment. Our Major Focus is on Forest Ecology and Environmental Remediation.
Forest Ecology is looking at a relict pristine wet zone forest as well as the dry forests in Sri Lanka. We also have an Arboretum in Dambulla, which is a model for forest restoration. We are also studying the ecology of serpentine sites in Sri Lanka to understand the accumulation of heavy metals in plant species in this unique habitat.
The Environmental Remediation project is exploring the role of plants in phytoremediation as well as plant-based biosorbents to bioremediate heavy metals and textile dyes from the aquatic environment.
Under Other Research we are conducting studies on the Impact of climate change – looking at historical trends in the local climate using baseline data and controlling the spread of dengue in Sri Lanka. The latter is part of a mega project implemented nationally. Besides looking at the socio-economic associations with the spread of the disease a small aquatic organism called copepods are being investigated as potential predators of the mosquito larvae.
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