“The closest known Earth analog to the possible Martian meteorite bacteria
is a critter known as bacterial strain MV-1. Magnetite produced by MV-1
resembles magnetite in *some* of those “fossil” blobs found in the Allan
Hills Martian meteorite (both in size and shape).”
BBC NEWS | Science/Nature | Earth could seed Titan with life
BTW: If there are any that doubt that some microbes cannot survive in a
space environment for long periods of time:
“The Long Duration Exposure Facility (LDEF), a NASA research satellite launched in the 1980s, showed that bacterial spores remain viable in space for at *least* 6 years (after 6 years, the satellite was retrieved). The spores were generally un[a]ffected by vacuum, heat, cold, X-rays, gamma rays, solar wind, and cosmic rays. The only thing that negatively affected the spores was ultraviolet radiation. But any spores trapped deep within fissures in an Earth rock would be protected from UV.”
–Phil Bigelow, on the Dinosaur Mailing List