[meteorite-list] Is Bacteria Recently Cultured From A Meteorite Just Little Earthlings?

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Thu Apr 22 09:46:24 2004
Message-ID: <200105141549.IAA04076_at_zagami.jpl.nasa.gov>

http://www.newscientist.co.uk/dailynews/news.jsp?id=ns9999725

Alien Visitors
By Debora MacKenzie
New Scientist
May 11, 2001

Live bacteria are cultured from a meteorite, but are they just little
Earthlings?

Live bacteria have been found inside a meteorite in a Naples museum,
according to two researchers at the University of Naples - and they claim
the bacteria are not from Earth.

If these really were the first alien bugs, it could dramatically settle the
controversial theory that life colonised Earth from space. But British
geologists, who found local bacteria living inside a meteorite in Antarctica
last year, caution that the Italians may simply have observed little
Earthlings.

Bruno D'Argenio, a geologist, and Giuseppe Geraci, a molecular biologist,
say they cultured bacteria from a meteorite kept at the mineralogical museum
in Naples. The bacteria were wedged inside the crystal structure of
minerals, but were resurrected when a sample of the rock was placed in a
culture medium. They formed colonies and were susceptible to antibiotics.

The team put out a press release with these observations this week, but have
not yet reported their methods to colleagues. D'Argenio will present them to
a meeting on extraterrestrial biology in Frascati, Italy later in May.

Extreme temperatures

The proof that the bacteria were not terrestrial, the team claims, was that
they survived when the sample was sterilised at 950 °C and washed with
alcohol. Bacteria that arrive from space should survive high heat, they
argue, while the alcohol would eliminate surface-dwelling Earth microbes.

But David Wynn-Williams of the British Antarctic Survey says Earth bacteria
could easily have invaded the structure of the rock as it lay in the museum,
to depths that were not affected by the heat or alcohol.

He and colleagues found actinomycete bacteria inside the crystals of a
Martian meteorite last year, which looked exactly like Antarctic soil
bacteria, and grew on encountering moisture.

Gene test

The Italian team also claims their bacteria's DNA is unlike any on Earth.
"But without the experimental details, we really cannot say," says Luigi
Colangelli of the Capodimonte Observatory in Naples.

"I believe we will find evidence of life elsewhere," says Wynn-Williams.
"But it almost requires keeping a meteorite sterile from the moment it
lands."

This difficult task could get harder. Evidence has recently emerged of the
escalating black market trade in stolen meteorites.
Received on Mon 14 May 2001 11:49:21 AM PDT