Fig. 1.

End-point fluorescence measured in a panel of a microfluidic digital PCR array. (A) The measured end-point fluorescence from the rRNA channel (right half of each chamber, with the left half masked) and the terminase channel (left half of each chamber, with the right half masked) in a microfluidic array panel. Each panel in the array (1 of 12) consists of 765 reaction chambers 150 µm by 150 µm by 270 µm (6 nl). Retrieved colocalizations are outlined in orange, and positive rRNA chambers randomly selected for retrieval are outlined in gray. FA indicates false alarm (a probable terminase primer-dimer). (B) Normalized amplification curves of all chambers in (A) after linear derivative baseline correction (red, viral; green, rRNA). (C) Specific physical associations between a bacterial cell and the viral marker gene resulting in colocalization include, for example, an attached or assembling virion, injected DNA, an integrated prophage, or a plasmid containing the viral marker gene.