Abstract: Novel polyketides and novel methods of efficiently producing both new and known polyketides, using recombinant technology, are disclosed. In particular, a novel host-vector system is described which is used to produce polyketide synthases which in turn catalyze the production of a variety of polyketides.

Abstract: A device is provided for maintaining a volume of gas dissolved in a fluid at a predetermined partial pressure. The device includes a first sealable, gas-tight pouch containing the fluid and a second sealable, gas-tight pouch encasing the first pouch and providing a space between the first and second pouches. The space may be charged with an atmosphere containing a volume of the gas dissolved in the fluid that is greater than the volume of dissolved gas, at a partial pressure that is substantially the same as the partial pressure of the dissolved gas. A method is also provided for using the device to maintain a volume of a gas dissolved in a fluid at a predetermined partial pressure.