Research scientists at Lawrence Livermore National Lab have been working on a detection technology that will be able to detect and identify just about any organism, including viruses, bacteria, fungi, and protozoa based on their endogeneous nucleic acid sequences. The current version of the Lawrence Livermore Microbial Detection Array (LLMDA), as the device is being called, contains 388,000 probes that together can screen for about 2,000 viruses and 900 bacteria. Moreover, there’s nothing stopping the scientists (except funding, of course) in expanding the device to include all known microorganisms of interest.
Currently, Slezak’s [Tom Slezak, LLNL’s associate program leader for Informatics] team is testing a next-generation LLMDA that boasts 2.1 million probes. This version contains probes representing about 178,000 viral sequences from some 5,700 viruses, and about 785,000 bacterial sequences from thousands of bacteria.
The latest LLMDA version also encompasses fungi and protozoa – with probes representing about 237,000 fungal sequences from thousands of fungi and about 202,000 protozoa sequences from 75 protozoa.
The LLMDA process starts with the purification of DNA or RNA from a sample, such as sputum or blood. The sample is next labeled with a fluorescent dye and hybridized on the microarray at 42 degrees C or about 107.6 degrees Fahrenheit. In turn, a fluorescent scanner and analysis software are used to detect the probes that have lit up, identifying the presence of viral or bacterial sequences.
Press release: New LLNL detection technology identifies bacteria, viruses, other organisms within 24 hours…
Relevant abstract in Journal of Virology: Viral nucleic acids in live-attenuated vaccines: detection of minority variants and an adventitious virus.