| March 2, 2001
WASHINGTON (AP) - Genes extracted from soil bacteria and slipped
into a laboratory microbe have given pharmaceutical scientists a new
source of a group of natural compounds that are used to make several
major drugs.
The compounds - polyketides - used in drug production are usually
made by certain bacteria families. Manipulating the genes in these
bacteria to cause them to form particular types of the compounds has
led to development of drugs that now account for about $10 billion
in annual sales.
Many of the drug compounds are difficult to synthesize, so
pharmaceutical companies use natural organisms, such as soil
bacteria, to make the drugs in huge, industrial-sized vats.
But some key polyketide-making bacteria are hard and slow to
grow, and they also resist the genetic manipulation necessary to
make the drugs. This makes industrial production of drug compounds
from these organisms difficult and more expensive.
That problem may be solved, according to a study appearing Friday
in the journal Science.
Researchers at Stanford University in California and at Brown
University in Providence, R.I., have found a way to use a common
bacteria, E. coli, to do the work of the more finicky soil bacteria.
The scientists put into E. coli genes from three different soil
microorganisms, changed some of the natural genes in E. coli and
produced a laboratory culture that churns out polyketides at a high
rate.
The work means that E. coli, an easily manipulated bacteria
well-known to researchers, could be substituted for the more
difficult polyketide-making bacteria, the authors said.
Heinz Floss, a bioorganic chemist at the University of
Washington, Seattle, said in Science that the discovery is ``a real
breakthrough.''
Co-authors of the study are Blaine A. Pfeifer, Suzanne J.
Admiraal, Hugo Gramajo and Chaitan Khosla of Stanford, and David E.
Cane of Brown.
Copyright 2001 The Associated Press. All rights
reserved. | 
