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.