DETERMINATION OF SEQUENCE DISTRIBUTIONS IN BACTERIAL COPOLYESTERS CONTAINING HIGHER ALKYL AND ALKENYL PENDANT GROUPS

The sequence distributions of microbial copolyesters produced by Pseudomonas oleovorans grown with (a) nonanoic acid (NA), (b) an equimolar mixture of NA and octanoic acid (OA), or (c) 2:1 mixtures of 10-undecenoic acid (UD) with either NA or OA were determined by analyzing the oligomers prepared by partial pyrolysis of these copolyesters using fast atom bombardment mass spectrometry. Oligomers up to tetramers were identified, and the amounts of these oligomers were used to calculate repeating unit compositions and sequence distributions. The sequence distributions in these copolyesters followed Bernoullian statistics, indicating that they were random copolymers. No ester exchange occurred during the pyrolysis.