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Protein Import into the Peroxisomes

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Peroxisomal Protein Import:
Peroxisomes lack the genetic machinery required to code for their own proteins. Hence, most peroxisomal membrane, lumenal and transmembrane proteins are synthesized in the cytoplasm or ER and transported to the peroxisome...
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Protein Kinases and Phosphatases

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Protein Kinases and Phosphatases02:54

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Fluorescence-based Monitoring of PAD4 Activity via a Pro-fluorescence Substrate Analog
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Fluorescence-based Monitoring of PAD4 Activity via a Pro-fluorescence Substrate Analog

Published on: November 5, 2014

Prolyl 4-hydroxylase.

Kelly L Gorres1, Ronald T Raines

  • 1Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706-1544, USA.

Critical Reviews in Biochemistry and Molecular Biology
|March 5, 2010
PubMed
Summary
This summary is machine-generated.

Prolyl 4-hydroxylase (P4H) catalyzes the most common irreversible protein modification in humans, yielding hydroxyproline (Hyp). This review covers P4H enzymes, their diverse substrates, and the wide-ranging biochemical impacts of Hyp.

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Overexpression and Purification of Human Cis-prenyltransferase in Escherichia coli
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Overexpression and Purification of Human Cis-prenyltransferase in Escherichia coli
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Overexpression and Purification of Human Cis-prenyltransferase in Escherichia coli

Published on: August 3, 2017

Area of Science:

  • Biochemistry
  • Molecular Biology
  • Protein Chemistry

Background:

  • Posttranslational modifications (PTMs) are crucial for protein function, often acting as reversible switches.
  • Prolyl hydroxylation, catalyzed by prolyl 4-hydroxylase (P4H), is a unique, irreversible PTM in humans.
  • This modification yields (2S,4R)-4-hydroxyproline (Hyp), impacting protein structure and interactions.

Purpose of the Study:

  • To review the enzymes responsible for prolyl hydroxylation.
  • To elucidate the chemical and biochemical consequences of hydroxyproline formation.
  • To highlight the diverse roles and substrates of P4H.

Main Methods:

  • Literature review of enzymic catalysts of prolyl hydroxylation.
  • Analysis of biochemical consequences of hydroxyproline formation.
  • Examination of protein substrates and their functional alterations.

Main Results:

  • P4H enzymes catalyze the abundant, irreversible hydroxylation of proline residues.
  • Hydroxyproline is found in diverse proteins, including collagen, elastin, and argonaute 2.
  • Prolyl hydroxylation affects protein conformation, protein-protein interactions, and enables further modifications.
  • P4H substrates include hypoxia-inducible factor alpha, potentially impacting oxygen sensing.
  • P4Hs are conserved across animals, plants, and microbes.

Conclusions:

  • Prolyl hydroxylation is a fundamental and widespread posttranslational modification with significant functional implications.
  • The irreversible nature of Hyp formation distinguishes it from typical reversible PTMs.
  • Understanding P4H activity is key to comprehending diverse biological processes, from structural protein stability to gene regulation.