The early genomics studies that began appearing in the 1980s progressed exponentially to the current state where the genome sequences of several hundred microbes, numerous eukaryotics, and thousands of viruses are available. Current estimates are that there are hundreds of partial genomes available and many other genome sequencing projects are also in progress. The real launch of the genomic era, however, began in the early 1990s with the availability of the complete genome sequence of Haemophilus influenzae.

This study which was mind shattering at the time has now become routine protocol in many laboratories.

Genomics really came of age when we began to witness a greater level of microbial diversity within species than previously anticipated, lateral gene transfer, and the significance of phage and viral genomics. The field of genomics which gave us the first genome of a free living organism also laid the foundation for generating genomic sequence data from whole environments without first using a culturing step, a field of research now known as 'metagenomics'.

The term metagenomics was first used in the late 1990s, and was defined as the genomic analysis of microorganisms by direct extraction and cloning of DNA from an assemblage of microorganisms. The availability of 'next generation' sequencing technologies such as 454 pyrosequencing have made it such that a cloning step is no longer essential for metagenomic projects.

Further reading:

• Environmental Molecular Microbiology
• Metagenomics: Theory, Methods and Applications

Labels: genomics, metagenomics