Mechanism of cis-prenyltransferase reaction probed by substrate analogues

Journal Article · Fri Oct 01 04:00:00 EDT 2010 · Biochemical and Biophysical Research Communications

DOI:https://doi.org/10.1016/J.BBRC.2010.09.001· OSTI ID:22202797

Lu, Yen-Pin; Liu, Hon-Ge ^[1]; Teng, Kuo-Hsun ^[2]; Liang, Po-Huang ^[1]

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1. Institute of Biochemical Sciences, National Taiwan University, Taipei 106, Taiwan, ROC (China)
2. Institute of Biological Chemistry, Academia Sinica, Taipei 115, Taiwan, ROC (China)

Research highlights: {yields} The extremely slow trans-OPPS reaction using 2-Fluoro-FPP supports the sequential mechanism with the carbocation intermediate. {yields} The similar UPPS reaction rate under single turnover supports the concerted mechanism, without the carbocation intermediate. {yields} The secondary kinetic isotope effect also supports associate transition state for UPPS reaction, without the carbocation intermediate. -- Abstract: Undecaprenyl pyrophosphate synthase (UPPS) is a cis-type prenyltransferases which catalyzes condensation reactions of farnesyl diphosphate (FPP) with eight isopentenyl pyrophosphate (IPP) units to generate C{sub 55} product. In this study, we used two analogues of FPP, 2-fluoro-FPP and [1,1-{sup 2}H{sub 2}]FPP, to probe the reaction mechanism of Escherichia coli UPPS. The reaction rate of 2-fluoro-FPP with IPP under single-turnover condition is similar to that of FPP, consistent with the mechanism without forming a farnesyl carbocation intermediate. Moreover, the deuterium secondary KIE of 0.985 {+-} 0.022 measured for UPPS reaction using [1,1-{sup 2}H{sub 2}]FPP supports the associative transition state. Unlike the sequential mechanism used by trans-prenyltransferases, our data demonstrate E. coli UPPS utilizes the concerted mechanism.

• OSTI ID: 22202797
• Journal Information: Biochemical and Biophysical Research Communications, Journal Name: Biochemical and Biophysical Research Communications Journal Issue: 4 Vol. 400; ISSN 0006-291X; ISSN BBRCA9
• Country of Publication: United States
• Language: English

Related Subjects

60 APPLIED LIFE SCIENCES
DEUTERIUM
ESCHERICHIA COLI
ISOTOPE EFFECTS
PHOSPHATES
REACTION KINETICS
SUBSTRATES
THIN-LAYER CHROMATOGRAPHY