摘要
Objective:Resident microorganisms live in dynamic harmony with their hosts to influence various physical and psychological health aspects.The majority of the resident microbes are found in the digestive tract,aka the gut of mammals.If and when perturbed,the composition of gut microbiota could jeopardize the physiological balance or homeostasis.In this article,we aim to establish how different diseases could be accompanied by notable changes in gut microbial composition and lend insight into microbial regulation of health.Methods:Literature search was done in PubMed using relevant keywords and summarized in tabular form as well as in narration.Results:We try to focus on the concept of microbial and metabolite biomarkers for diseases.We also try to capture the renewed perspective of good and harmful microorganisms in the context of host health.We have presented a comparative network analysis of microbial roles in select diseases.Recent findings also suggested that the growth of some traditionally disease-causing pathogenic microorganisms promotes health in other human communities.We have listed major taxa of gut microbes in communities worldwide,which signifies that gut microbiota can be healthy or harmful depending on the urbanization and ethnicity of the hosts.The traditional and current schools of thoughts are both limited by the technology of metagenomic studies;we have elucidated some of their shortcomings.Conclusion:Research in the field of gut microbiota must take into account the different populations and the changing narrative of healthy and harmful microbes.