Sequenom is developing a high-speed "bacterial fingerprinting" technique based on mass spectrometry that can be used to rapidly identify the DNA of subtly different strains of bacteria or viruses.
Dr Venter's was the real McCoy: when he put the viral DNA into host cells they started to spit out new viruses just as self-destructively as cells infected with the natural Phi-X174.
They also took what is known as a metagenomic approach, filtering through all the fragments of DNA present and identifying those that could have come from bacteria, fungi, or viruses.