The Judas Strain (Sigma Force 4)

Devesh awoke the sleeping computers with the tap of a few buttons, drawing her attention back. All three monitors bloomed to a brilliant glare in the dim room.

"Dr. Barnhardt... or Henri, if I may presume ... ?" Devesh glanced back.

The toxicologist merely shrugged.

Devesh continued. "Henri, I must commend you on your assessment of the true threat hidden within the shroud of the toxic assault. It had taken our scientists weeks to ascertain what you managed to discern in less than twenty-four hours."

Lisa's skin went cold. Weeks. So their captors had been aware of the threat at the island long before the full crisis broke. But what did any of this have to do with the Guild?

"Of course, we did not so much appreciate the general alarm you raised, reaching all the way to Washington. It required accelerating our timetable.. . and some improvisation. Like utilizing the scientific talent here and merging it with my own. But so be it. We must move quickly if there is to be any hope."

"Hope for what?" Lisa finally asked.

"Let me show you, my dear." Devesh patted one of the two chairs, inviting her to sit.

She remained standing, but he seemed to take no offense, busy with the computer keyboard. On the center monitor, a video began playing. It depicted a dense microscopic field of twitching chains of rod-shaped bacteria.

"How much do you know about anthrax?" Devesh asked, glancing back.

Lisa's skin went cold at his question.

Henri answered, "Bacillus anthracis. It mostly infects ruminants. Cows, goats, sheep. But spores can also infect humans. Often proving fatal."

It was a clinical assessment, devoid of emotion. But Lisa noted the tense hold to the toxicologist's shoulders.

Devesh nodded. "Bacillus species are found worldwide in soil. Harmless for the most part. For example, here is one such benign organism, Bacillus cereus."

The screen image changed to a microscopic close-up of a single bacterium. Rod-shaped with a thin membranous wall, the cell's DNA strands were stained to stand out in the center.

"Like other members of the species, this little bug can be found in gardens around the world. Happily feeding on microorganisms and nutrients in the soil. It causes no harm to anything larger than an amoeba. But its brother, Bacillus anthracis—" Devesh clicked to bring up another image, side by side, with the first, a second bacterium that looked identical.

"Here is the organism that causes anthrax," he continued, "one of the most deadly bacterium on the planet. It shares the same genetic code with its peaceful, garden-dwelling brother." Devesh tapped the two cells' stained twists of DNA. "Gene by gene, nearly identical. So why does one kill and the other remain harmless?"

Over a shoulder, Devesh stared back at Lisa and Henri.

Lisa shook her head. Henri remained silent.

Devesh nodded as if satisfied by their reticence. Turning back, he toggled a key and the anthrax bacterium zoomed on the screen. The mass of DNA swelled on the monitor. Within the cytoplasm of the interior cell, separate from the main tangle of DNA, floated two perfect rings of genetic material, like a tiny pair of eyes staring back at them.

"Plasmids," Henri said, naming the rings.

Lisa's brow tightened as she was forced to draw upon her pre-med education. As well as she could recall, plasmids were circular strands of DNA separate from main chromosomal DNA. The free-floating bits of genetic code were unique to bacteria. Their role was still poorly understood.

Devesh continued. "These two plasmids—pXoi and pXo2—are what turn ordinary Bacillus species into superkillers. Remove these two rings, and anthrax transforms back into an innocent organism, living happily in any garden. Put those same plasmids into any friendly Bacillus and the bug turns into a killer."

Devesh finally swung around to face them. "So I ask you, where did these extraneous and deadly bits come from?"

Lisa answered, intrigued despite herself. "Can't plasmids be shared directly from one bacterium to another?"

"Certainly. But what I meant was, how did these bacteria first acquire these foreign bits of genetic material? What's their original source?"

Henri stirred, moving closer to study the screens. "The evolutionary origin of plasmids remains a mystery, but the current theory is that they were acquired from viruses. Or more specifically bacteriophages, a category of viruses that only infect bacteria."

"Exactly!" Devesh turned back to the screen. "It's been theorized that, sometime in the ancient past, a viral bacteriophage injected a peaceful Bacillus with this deadly pair of plasmids, creating a new monster in the biosphere and transforming a sweet little garden bug into a killer."

Devesh tapped more rapidly, clearing the screen. "And anthrax isn't the only bacterium thus infected. The bacterium that causes the black plague, Yersinia pestis ... its virulence is also enhanced by a plasmid."

Lisa felt a prickling chill as realization dawned. All this talk of transforming bacteria reminded her of the patients on the ship. The girl with seizures from vinegar bacteria, the woman with choleric dysentery from yogurt bacteria, the John Doe whose skin bacteria were eating his legs away .. .

"Are you suggesting it's happening here again?" she mumbled. "This same corruption of bacteria."

Devesh nodded. "Indeed. Something has risen again out of the depths of the sea, something with the ability to turn all bacteria deadly."

Lisa remembered Henri's example of how prevalent bacteria were in the world, how 90 percent of the cells in our own bodies were composed of bacteria. Nonhuman. If that tide should shift against us . . .

Devesh continued. "From studying the genetics of anthrax and other toxic bacteria, microbiologists have predicted the existence of an ancient strain of viruses. A strain that created the early ancestors of anthrax and other plague bacteria. Scientists have even coined a name for this ancient strain of viruses, one that turns friend into foe: the Judas Strain."

Henri must have read something in Devesh's face, a brightness to his eyes, an excitement. He straightened. "Something tells me you've isolated the causative agent in the outbreak here, haven't you? This Judas Strain. Or you wouldn't be here."

"We think so."

Devesh tapped another two keys. The bacterium vanished, replaced with a rotating figure on the screen, an image from an electron micrograph, all in shades of silver. It made the organism depicted seem more mechanical than biological. It looked like some lunar lander. The main shell was geometric, an icosahedron, made up of twenty flat triangular pieces. Out from every corner stretched thin tendrils, spiked at the tips, made to latch on and pierce.