Molecular biology of ammonia oxidation by Nitrosomonas europaea

摘要

With the application of molecular biological techniques to N. europaea, rapid progress has been made in characterizing the genes involved in ammonia oxidation including their organization, sequence, and regulation. This information complements the body of biochemical data about ammonia oxidation in N. europaea that already exists. The regulation of amo expression in particular appears to be a complex event involving both different transcription patterns in conjunction with mKNA processing. Similarly, the two promoter types for the hao genes suggest that the copies of hao might respond to different environmental signals. However, the physiological significance of the presence of multiple copies of these genes remains unclear and is still under investigation. The nearly complete N. europaea genomic sequence has already begun to reveal a wealth of information about the physiology of TV. europaea. With this new genetic information in hand, the relationship between ammonia oxidation and other physiological process can now be explored with a view toward understanding some of the physiological consequences of the chemolithoautotrophic lifestyle that N. europaea has adopted.