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all marine mammal researchers receive feder- ior as a “long-term” change in a “species or expected to sign into law this week, says it al funding. Nor does the law ease the rules stock,” which could be impossible to deter- applies to military activity “or a scientific re- for scientists doing ocean research that af- mine, Steuer says. The report and the final bill fects mammals incidentally, says Penelope are “inconsistent,” agrees Donna Wieting of ducted by or on behalf of the Federal Govern- Dalton of the Consortium for Oceanographic the National Marine Fisheries Service, which ment.” But whether that encompasses any Research and Education in Washington, D.C.
must craft regulations to enforce the act. scientist with federal funding is up to “agen- Some critics also point to ambiguous lan- cies and lawyers” to decide, says Karen guage in a report accompanying the bill. For will be revisited next year, when Congress Steuer, a former House staffer who now ad- example, although the report discusses “bio- vises the National Environmental Trust in logically significant” impacts, a term scien- changes “are going to be very important” to Washington, D.C. In any case, she notes, not tists have pushed for, it defines altered behav- Triple-Threat Microbe Gained Powers From Another Bug
The long-dreaded superbug surfaced on a
biotics, including penicillin, methicillin, and identical to each other and similar to a men- ciprofloxacin, and it possessed the genetic acing S. aureus strain that commonly infects Staphylococcus aureus, cultured from foot ulcers on a diabetes patient in a Detroit dial- drug-susceptible S. aureus strains. called plasmids from the VRSA and E. fae- S. aureus commonly lives on the skin and calis strains, but not the susceptible S. au- vancomycin, one of the few antibiotics left in the noses of healthy people, causing noth- reus strain, had a gene called vanA that that reliably kills staph. Doctors rushed the wards off vancomycin. That suggested that strain to the Centers for Disease Control and hospitalized patients, it causes tens of thou- Prevention in Atlanta, and nine local and sands of infections each year, including seri- CDC public health officials scoured the dial- ous and sometimes fatal surgical-wound in- ysis center and tested more than 300 people fections, bloodstream infections, and pneu- searchers checked the plasmids for a mobile the patient had come in contact with, col- monia. Penicillin saved many patients, but genetic element called a transposon, a snip- pet of DNA that can jump out of one plas- mid and worm its way into another. As has been found in other vancomycin-resistant E. faecalis strains, this one hosted a plasmid with a transposon containing vanA. The transposon appeared in a plasmid in the new VRSA strain as well. Colleagues at The In- stitute for Genomic Research in Rockville, Maryland, sequenced the entire VRSA plas- mid, showing that the transposon was intact Together, the results suggest that E. fae- calis in the woman’s ulcer sidled up to S. au- reus and passed along its resistance plasmid.
Enzymes in S. aureus seem to have de- stroyed the foreign E. faecalis plasmid, but jumped, like a rat escaping a sinking ship, and infiltrated the S. aureus’s resident plas- Dangerous liaison. Vancomycin resistance probably jumped from E. fae-
mid to create a new hybrid. That created a calis to S. aureus via a plasmid (black loop) carrying a transposon (red) that nasty new S. aureus strain that can spread then infested the resident plasmid (blue).
readily in hospitals, resist almost all the ance genes to drugs available to kill it, and share its lecting samples to see if it had spread. It S. aureus on the skin of a mouse. “We be- weapons with S. aureus cousins that remain hadn’t. “We dodged another bullet,” says gan to anticipate that at some point we’d vulnerable to vancomycin. “What we’ve iso- clinical microbiologist Donald Low of the see high-level resistance moving into S. lated is really the triple threat,” Tenover says.
In the clinic, says Low, “it’s critical for laboratories to be on the lookout” for new S. aureus (VRSA) strain appeared, the detec- VRSA strains and for doctors to work to keep tive work began. Doctors isolated two strains them in check. Two antibiotics, linezolid CDC and colleagues found that the bug like- from the patient. One resisted almost all avail- (Zyvox) and quinupristin/dalfopristin (Syner- ly acquired the vancomycin-resistance trait able antibiotics. The other, from the woman’s cid), still stop VRSA, but it’s important that foot ulcer, resisted the same drugs plus vanco- drug companies step up efforts to develop al- settings, a dangerous alliance that health of- ternatives, he says: “Right now we’ve got ficials had long feared. The new S. aureus resistant E. faecalis from her foot ulcers.
something in our back pocket, but that could The two S. aureus strains were otherwise

Source: http://fire.biol.wwu.edu/trent/trent/triplethreat.pdf