Recent advances in the human microbiome - review

The human gut microbiome can be considered a 'new' internal organ, with a metabolic capacity exceeding that of the liver, or our primary connection to the environment, linking us to the world's ecology. The density of microbes within the colon is one of the highest in nature, and it is estimated that the number of microbes within our gut match or exceed that of our host human cell count, whilst their genetic machinery outnumbers our own by 100:1. This helps explain the remarkable new findings that show our microbiome not only affects the health and function of our intestines, but also has a strong influence on general body health through its close interaction with the gut immune system and through its production of bioactive metabolites that are absorbed and affect distant organ function. A state of dysbiosis can occur when its food source, fiberrich foods, becomes depleted and when oral antibiotics are used. Dysbiosis has been linked to an increasing list of human diseases, and in particular to 'westernized' diseases, such as colon cancer, allergy, diabetes, obesity, inflammatory bowel disease, and atherosclerosis, which pose the major threat to healthcare in the USA today

Comparative assessment of bacterial diversity associated with co-occurring eukaryotic hosts of Palk Bay origin.

Epibacterial communities of co-occurring eukaryotic hosts of Palk Bay origin (five seaweed species (Gracilaria sp, Padina sp, Enteromorpha sp, Sargassum sp, and Turbinaria sp) and one seagrass [Cymodaceae sp]) were analyzed for diversity and compared using 16S rRNA based Denaturant Gradient Gel Electrophoresis analysis. Diversity index revealed that Turbinaria sp hosts highest bacterial diversity while it was least in Gracilaria sp. The DGGE band profile showed that the epibacterial community differed considerably among the studied species. Statistical assessment using cluster analysis and Non-metric multidimensional scale analysis also authenticated the observed variability. Despite huge overlap, the composition of bacterial community structure differed significantly among the three closely related species namely Sargassum, Turbinaria and Padina. In addition, Enteromorpha and Sargassum, one being chlorophyta and the other phaeophyta showed about 80% similarity in bacterial composition. This differs from the general notion that epibacterial community composition will vary widely depending on the host phyla. The results extended the phenomenon of host specific epibacterial community irrespective of phylogeny and similarity in geographical location.