Blood In, Blood Out

Recently eaten: turkey chili
Recent annoyance:

Sorry for all the bloody posts recently. Must be all that talk of Jesus resurrection and Passover and everything. Well, they've made us o positive blood types obsolete. We used to be those special universal donors, and now, they come out with this blood type conversion jive. Sure, they'll save more lives. But what about our feelings?

Blood groups can be converted
Scientists have developed a way of converting one blood group into another.

The technique potentially enables blood from groups A, B and AB to be converted into group O negative, which can be safely transplanted into any patient.

The method, which makes use of newly discovered enzymes, may help relieve shortages of blood for transfusions.

The work, led by the University of Copenhagen, is reported in the journal Nature Biotechnology.

Using incompatible blood during a transfusion can put a patient's life in danger.

The blood cells of people with group A and B blood contain one of two different sugar molecules, which act as "antigens", triggering an immune system response.

People with AB blood have both types of molecule, while those with group O blood have neither.

People produce antibodies against the antigens they lack.

This means groups A, B and AB can only be given to patients with compatible blood, while O - as long as it is rhesus negative - can be given to anyone.

The new technique works by using bacterial enzymes to cut sugar molecules from the surface of red blood cells.

After a search of 2,500 fungi and bacteria the researchers discovered two bacteria - Elizabethkingia meningosepticum and Bacterioides fragilis - which contained potentially useful enzymes.

They found that enzymes from both bacteria were able to remove both A and B antigens from red blood cells.