Nature Reviews Microbiology 5, 782–791 (2007), doi: 10.1038/nrmicro1747

In the above article, the following passage of text on page 783 might have been misleading: 'The detection of high abundances of decomposer bacteria (106 per ml11) has led to the suggestion that the numbers and activity of primary producers (such as cyanobacteria and algae), decomposers (such as bacteria) and predators (such as viruses and protists) are similar (Fig. 1).' It should have read: 'The detection of high abundances of decomposer bacteria (106 per ml11) has led to the suggestion that every microlitre of seawater contains all the components of the microbial loop: primary producers (such as cyanobacteria and algae), decomposers (such as bacteria) and predators (such as viruses and protists) (Fig. 1).' The authors apologize to the readers for any confusion caused.