Abstract:
:Whole cell pyruvate decarboxylase (PDC) from Candida utilis enhanced the enzymatic production of (R)-phenylacetylcarbinol (PAC) in an aqueous/octanol biotransformation compared to the partially purified PDC especially for a lower range of initial activities (0.3-2.5 U/mL). With an initial activity of 1.1 U/mL and at a 1:1 phase volume ratio, whole cell PDC achieved a maximum specific PAC production of 42 mg/U (2.8 g/L/h) in comparison to 13 mg/U (0.9 g/L/h) for partially purified PDC. The enhanced performance of whole cell PDC was associated with high stability towards the substrate benzaldehyde. The strong PDC inactivation by benzaldehyde was minimal even when whole cells were broken as long as cell debris was not removed from the broken cells. Biotransformations with various cellular components added to partially purified PDC revealed that membrane components especially 2 mg/mL phosphatidylcholine enhanced PAC concentrations. The role of surfactants was further confirmed from the results with synthetic surfactant sodium bis(2-ethyl-1-hexyl)sulfosuccinate (AOT). It was apparent that the membrane components in whole cells were sufficient for optimal PAC production and no further surfactant addition is required for optimal performance.
journal_name
Biotechnol Bioengjournal_title
Biotechnology and bioengineeringauthors
Satianegara G,Rogers PL,Rosche Bdoi
10.1002/bit.20959subject
Has Abstractpub_date
2006-08-20 00:00:00pages
1189-95issue
6eissn
0006-3592issn
1097-0290journal_volume
94pub_type
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