Abstract:
:The enzymatic synthesis of polyesters from activated diesters and diols has been investigated. Differences between enzymatic synthesis and traditional chemical condensation processes are discussed. The disappearance of monomers during the initial phase of reaction indicates that enzyme has a higher specificity for transesterification of ester-terminated oligomers. During the intermediate phase, enzymatic polymerization involves a competition between diol and enzyme-bound water for the nucleophilic attack of the acyl enzyme intermediate. Competition between enzymatic transesterification and hydrolysis at different stages of polymerization in nonaqueous media is responsible for termination of polyesters with acid end-groups and also for limiting the polymer molecular weight. The resulting oligoester consists of chains that are either terminated with - OH groups and/or - COOH groups. We have used Matrix Assisted Laser Desorption/Ionization - Time of Flight Mass spectroscopy (MALDI-TOF) along with colorimetric titration techniques to determine the acidity of enzyme-synthesized polyesters. This paper addresses how the enzymatic polymerization proceeds, and compares our results to the growing literature in this field.
journal_name
Biotechnol Bioengjournal_title
Biotechnology and bioengineeringauthors
Chaudhary AK,Beckman EJ,Russell AJdoi
10.1002/(SICI)1097-0290(19970705)55:1<227::AID-BITsubject
Has Abstractpub_date
1997-07-05 00:00:00pages
227-39issue
1eissn
0006-3592issn
1097-0290journal_volume
55pub_type
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