Abstract
Escherichia coli thioesterase/protease I (TEP-I) is a lipolytic enzyme of the serine protease superfamily with Ser10, Asp154 and His157 as the catalytic triad residues. Based on comparison of the low-field 1H nuclear magnetic resonance spectra of two mutants (S10G and S12G) and two transition state analogue complexes we have assigned the exchangeable proton resonances at 16.3 ppm, 14.3 ppm, and 12.8 ppm at pH 3.5 to His157-Nδ1H, Ser10-OγH and His157-Nε2H, respectively. Thus, the presence of a strong Asp154-His157 hydrogen bond in free TEP-I was observed. However, Ser10-OγH was shown to form a H-bond with a residue other than His157-Nε2.
Original language | English |
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Pages (from-to) | 203-206 |
Number of pages | 4 |
Journal | FEBS Letters |
Volume | 528 |
Issue number | 1-3 |
DOIs | |
Publication status | Published - 2002 Sept 25 |
Externally published | Yes |
Keywords
- Lipolytic enzyme
- Low barrier hydrogen bond
- Nuclear magnetic resonance
- Serine protease
- Thioesterase
ASJC Scopus subject areas
- Biophysics
- Structural Biology
- Biochemistry
- Molecular Biology
- Genetics
- Cell Biology