Abstract
MonoTIM is a stable monomeric variant of the dimeric trypanosomal enzyme triose phosphate isomerase (TIM) with less, but significant, catalytic activity. It is known that in TIM, three residues, Lys 13 (loop 1), His 95 (loop 4), and Glu 167 (loop 6) are the crucial catalytic residues. In the wild-type TIM dimer, loop 1 and loop 4 are very rigid because of tight interactions with residues of the other subunit. Previous structural studies indicate that Lys 13 and His 95 have much increased conformational flexibility in monoTIM. Using site-directed mutagenesis, it is shown here that Lys 13 and His 95 are nevertheless essential for optimal catalysis by monoTIM: monoTIM-K13A is completely inactive, although it can still bind substrate analogues, and monoTIM-H95A is 50 times less active. The best inhibitors of wild-type TIM are phosphoglycolohydroxamate (PGH) and 2-phosphoglycolate (2PG), with KI values of 8 microM and 26 microM, respectively. The affinity of the monoTIM active site for PGH has been reduced approximately 60-fold, whereas for 2PG, only a twofold weakening of affinity is observed. The mode of binding, as determined by protein crystallographic analysis of these substrate analogues, shows that, in particular, 2PG interacts with Lys 13 and His 95 in a way similar but not identical to that observed for the wild-type enzyme. This crystallographic analysis also shows that Glu 167 has the same interactions with the substrate analogues as in the wild type. The data presented suggest that, despite the absence of the second subunit, monoTIM catalyzes the interconversion of D-glyceraldehyde-3-phosphate and dihydroxyacetone phosphate via the same mechanism as in the wild type.
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Selected References
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- Bash P. A., Field M. J., Davenport R. C., Petsko G. A., Ringe D., Karplus M. Computer simulation and analysis of the reaction pathway of triosephosphate isomerase. Biochemistry. 1991 Jun 18;30(24):5826–5832. doi: 10.1021/bi00238a003. [DOI] [PubMed] [Google Scholar]
- Blacklow S. C., Knowles J. R. How can a catalytic lesion be offset? The energetics of two pseudorevertant triosephosphate isomerases. Biochemistry. 1990 May 1;29(17):4099–4108. doi: 10.1021/bi00469a012. [DOI] [PubMed] [Google Scholar]
- Borchert T. V., Abagyan R., Jaenicke R., Wierenga R. K. Design, creation, and characterization of a stable, monomeric triosephosphate isomerase. Proc Natl Acad Sci U S A. 1994 Feb 15;91(4):1515–1518. doi: 10.1073/pnas.91.4.1515. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Borchert T. V., Abagyan R., Kishan K. V., Zeelen J. P., Wierenga R. K. The crystal structure of an engineered monomeric triosephosphate isomerase, monoTIM: the correct modelling of an eight-residue loop. Structure. 1993 Nov 15;1(3):205–213. doi: 10.1016/0969-2126(93)90021-8. [DOI] [PubMed] [Google Scholar]
- Borchert T. V., Kishan K. V., Zeelen J. P., Schliebs W., Thanki N., Abagyan R., Jaenicke R., Wierenga R. K. Three new crystal structures of point mutation variants of monoTIM: conformational flexibility of loop-1, loop-4 and loop-8. Structure. 1995 Jul 15;3(7):669–679. doi: 10.1016/s0969-2126(01)00202-7. [DOI] [PubMed] [Google Scholar]
- Borchert T. V., Pratt K., Zeelen J. P., Callens M., Noble M. E., Opperdoes F. R., Michels P. A., Wierenga R. K. Overexpression of trypanosomal triosephosphate isomerase in Escherichia coli and characterisation of a dimer-interface mutant. Eur J Biochem. 1993 Feb 1;211(3):703–710. doi: 10.1111/j.1432-1033.1993.tb17599.x. [DOI] [PubMed] [Google Scholar]
- Collins K. D. An activated intermediate analogue. The use of phosphoglycolohydroxamate as a stable analogue of a transiently occurring dihydroxyacetone phosphate-derived enolate in enzymatic catalysis. J Biol Chem. 1974 Jan 10;249(1):136–142. [PubMed] [Google Scholar]
- Davenport R. C., Bash P. A., Seaton B. A., Karplus M., Petsko G. A., Ringe D. Structure of the triosephosphate isomerase-phosphoglycolohydroxamate complex: an analogue of the intermediate on the reaction pathway. Biochemistry. 1991 Jun 18;30(24):5821–5826. doi: 10.1021/bi00238a002. [DOI] [PubMed] [Google Scholar]
- Joseph-McCarthy D., Lolis E., Komives E. A., Petsko G. A. Crystal structure of the K12M/G15A triosephosphate isomerase double mutant and electrostatic analysis of the active site. Biochemistry. 1994 Mar 15;33(10):2815–2823. doi: 10.1021/bi00176a010. [DOI] [PubMed] [Google Scholar]
- Joseph D., Petsko G. A., Karplus M. Anatomy of a conformational change: hinged "lid" motion of the triosephosphate isomerase loop. Science. 1990 Sep 21;249(4975):1425–1428. doi: 10.1126/science.2402636. [DOI] [PubMed] [Google Scholar]
- Knowles J. R. Enzyme catalysis: not different, just better. Nature. 1991 Mar 14;350(6314):121–124. doi: 10.1038/350121a0. [DOI] [PubMed] [Google Scholar]
- Lambeir A. M., Opperdoes F. R., Wierenga R. K. Kinetic properties of triose-phosphate isomerase from Trypanosoma brucei brucei. A comparison with the rabbit muscle and yeast enzymes. Eur J Biochem. 1987 Oct 1;168(1):69–74. doi: 10.1111/j.1432-1033.1987.tb13388.x. [DOI] [PubMed] [Google Scholar]
- Lewis D. J., Lowe G. Inhibition of fructose-1,6-bisphosphate aldolase from rabbit muscle and Bacillus stearothermophilus. Eur J Biochem. 1977 Oct 17;80(1):119–133. doi: 10.1111/j.1432-1033.1977.tb11864.x. [DOI] [PubMed] [Google Scholar]
- Lodi P. J., Chang L. C., Knowles J. R., Komives E. A. Triosephosphate isomerase requires a positively charged active site: the role of lysine-12. Biochemistry. 1994 Mar 15;33(10):2809–2814. doi: 10.1021/bi00176a009. [DOI] [PubMed] [Google Scholar]
- Nickbarg E. B., Davenport R. C., Petsko G. A., Knowles J. R. Triosephosphate isomerase: removal of a putatively electrophilic histidine residue results in a subtle change in catalytic mechanism. Biochemistry. 1988 Aug 9;27(16):5948–5960. doi: 10.1021/bi00416a019. [DOI] [PubMed] [Google Scholar]
- Noble M. E., Zeelen J. P., Wierenga R. K. Structures of the "open" and "closed" state of trypanosomal triosephosphate isomerase, as observed in a new crystal form: implications for the reaction mechanism. Proteins. 1993 Aug;16(4):311–326. doi: 10.1002/prot.340160402. [DOI] [PubMed] [Google Scholar]
- Pompliano D. L., Peyman A., Knowles J. R. Stabilization of a reaction intermediate as a catalytic device: definition of the functional role of the flexible loop in triosephosphate isomerase. Biochemistry. 1990 Apr 3;29(13):3186–3194. doi: 10.1021/bi00465a005. [DOI] [PubMed] [Google Scholar]
- Studier F. W., Moffatt B. A. Use of bacteriophage T7 RNA polymerase to direct selective high-level expression of cloned genes. J Mol Biol. 1986 May 5;189(1):113–130. doi: 10.1016/0022-2836(86)90385-2. [DOI] [PubMed] [Google Scholar]
- Vriend G. WHAT IF: a molecular modeling and drug design program. J Mol Graph. 1990 Mar;8(1):52-6, 29. doi: 10.1016/0263-7855(90)80070-v. [DOI] [PubMed] [Google Scholar]
- Waley S. G. Refolding of triose phosphate isomerase. Biochem J. 1973 Sep;135(1):165–172. doi: 10.1042/bj1350165. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wierenga R. K., Borchert T. V., Noble M. E. Crystallographic binding studies with triosephosphate isomerases: conformational changes induced by substrate and substrate-analogues. FEBS Lett. 1992 Jul 27;307(1):34–39. doi: 10.1016/0014-5793(92)80897-p. [DOI] [PubMed] [Google Scholar]
- Williams J. C., McDermott A. E. Dynamics of the flexible loop of triosephosphate isomerase: the loop motion is not ligand gated. Biochemistry. 1995 Jul 4;34(26):8309–8319. doi: 10.1021/bi00026a012. [DOI] [PubMed] [Google Scholar]
- Wolfenden R. Transition state analogues for enzyme catalysis. Nature. 1969 Aug 16;223(5207):704–705. doi: 10.1038/223704a0. [DOI] [PubMed] [Google Scholar]
- Zabori S., Rudolph R., Jaenicke R. Folding and association of triose phosphate isomerase from rabbit muscle. Z Naturforsch C. 1980 Nov-Dec;35(11-12):999–1004. doi: 10.1515/znc-1980-11-1224. [DOI] [PubMed] [Google Scholar]