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Related Experiment Video

Updated: Mar 13, 2026

Specificity Analysis of Protein Lysine Methyltransferases Using SPOT Peptide Arrays
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Substrate scope for trimethyllysine hydroxylase catalysis.

Abbas H K Al Temimi1, Bas J G E Pieters1, Y Vijayendar Reddy1

  • 1Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands. j.mecinovic@science.ru.nl.

Chemical Communications (Cambridge, England)
|October 13, 2016
PubMed
Summary
This summary is machine-generated.

Trimethyllysine hydroxylase (TMLH) hydroxylates trimethyllysine for carnitine production. Studies show TMLH can also process other trimethyllysine analogues, expanding its known substrate range in this vital metabolic pathway.

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Area of Science:

  • Biochemistry
  • Enzymology
  • Metabolic Pathways

Background:

  • Trimethyllysine hydroxylase (TMLH) is crucial for carnitine biosynthesis.
  • TMLH is a non-haem Fe(ii) and 2-oxoglutarate dependent oxygenase.
  • It catalyzes the C-3 hydroxylation of l-trimethyllysine.

Purpose of the Study:

  • To investigate the substrate specificity of human TMLH.
  • To determine if TMLH accepts analogues of its natural substrate, l-trimethyllysine.

Main Methods:

  • Enzyme kinetics studies.
  • Analysis of trimethyllysine analogues as substrates for human TMLH.

Main Results:

  • Human TMLH demonstrates activity on substrates beyond l-trimethyllysine.
  • The enzyme hydroxylates specific trimethyllysine analogues.

Conclusions:

  • TMLH possesses a broader substrate specificity than previously understood.
  • This finding has implications for understanding carnitine biosynthesis and related metabolic processes.