St Andrews Research Repository

St Andrews University Home
View Item 
  •   St Andrews Research Repository
  • University of St Andrews Research
  • University of St Andrews Research
  • University of St Andrews Research
  • View Item
  •   St Andrews Research Repository
  • University of St Andrews Research
  • University of St Andrews Research
  • University of St Andrews Research
  • View Item
  •   St Andrews Research Repository
  • University of St Andrews Research
  • University of St Andrews Research
  • University of St Andrews Research
  • View Item
  • Login
JavaScript is disabled for your browser. Some features of this site may not work without it.

Kinetics and structure of a cold-adapted hetero-octameric ATP phosphoribosyltransferase

Thumbnail
View/Open
Revised_Manuscript_RGdS_AM.pdf (1.224Mb)
Date
07/02/2017
Author
Stroek, Rozanne
Ge, Ying
Talbot, P. D.
Glok, M. K.
Bernas, K. E.
Thomson, Catherine M.
Gould, Eoin R.
Alphey, Magnus S.
Liu, Huanting
Florence, Gordon J.
Naismith, James H.
da Silva, R. G.
Keywords
QD Chemistry
QH301 Biology
DAS
Metadata
Show full item record
Abstract
Adenosine 5′-triphosphate phosphoribosyltransferase (ATPPRT) catalyzes the first step in histidine biosynthesis, the condensation of ATP and 5-phospho-α-d-ribosyl-1-pyrophosphate to generate N1-(5-phospho-β-d-ribosyl)-ATP and inorganic pyrophosphate. The enzyme is allosterically inhibited by histidine. Two forms of ATPPRT, encoded by the hisG gene, exist in nature, depending on the species. The long form, HisGL, is a single polypeptide chain with catalytic and regulatory domains. The short form, HisGS, lacks a regulatory domain and cannot bind histidine. HisGS instead is found in complex with a regulatory protein, HisZ, constituting the ATPPRT holoenzyme. HisZ triggers HisGS catalytic activity while rendering it sensitive to allosteric inhibition by histidine. Until recently, HisGS was thought to be catalytically inactive without HisZ. Here, recombinant HisGS and HisZ from the psychrophilic bacterium Psychrobacter arcticus were independently overexpressed and purified. The crystal structure of P. arcticus ATPPRT was determined at 2.34 Å resolution, revealing an equimolar HisGS–HisZ hetero-octamer. Steady-state kinetics indicate that both the ATPPRT holoenzyme and HisGS are catalytically active. Surprisingly, HisZ confers only a modest 2–4-fold increase in kcat. Reaction profiles for both enzymes cannot be distinguished by 31P nuclear magnetic resonance, indicating that the same reaction is catalyzed. The temperature dependence of kcat shows deviation from Arrhenius behavior at 308 K with the holoenzyme. Interestingly, such deviation is detected only at 313 K with HisGS. Thermal denaturation by CD spectroscopy resulted in Tm’s of 312 and 316 K for HisZ and HisGS, respectively, suggesting that HisZ renders the ATPPRT complex more thermolabile. This is the first characterization of a psychrophilic ATPPRT.
Citation
Stroek , R , Ge , Y , Talbot , P D , Glok , M K , Bernas , K E , Thomson , C M , Gould , E R , Alphey , M S , Liu , H , Florence , G J , Naismith , J H & da Silva , R G 2017 , ' Kinetics and structure of a cold-adapted hetero-octameric ATP phosphoribosyltransferase ' , Biochemistry , vol. 56 , no. 5 , pp. 793-803 . https://doi.org/10.1021/acs.biochem.6b01138
Publication
Biochemistry
Status
Peer reviewed
DOI
https://doi.org/10.1021/acs.biochem.6b01138
ISSN
0006-2960
Type
Journal article
Rights
Copyright © 2017, American Chemical Society. This work is made available online in accordance with the publisher’s policies. This is the author created, accepted version manuscript following peer review and may differ slightly from the final published version. The final published version of this work is available at https://doi.org/10.1021/acs.biochem.6b01138
Description
This work was supported by the University of St Andrews and a Leverhulme Trust grant (RL-2012-025) to G.J.F. R.S. was the recipient of an Erasmus Undergraduate Fellowship.
Collections
  • University of St Andrews Research
URI
http://hdl.handle.net/10023/12496

Items in the St Andrews Research Repository are protected by copyright, with all rights reserved, unless otherwise indicated.

Advanced Search

Browse

All of RepositoryCommunities & CollectionsBy Issue DateNamesTitlesSubjectsClassificationTypeFunderThis CollectionBy Issue DateNamesTitlesSubjectsClassificationTypeFunder

My Account

Login

Open Access

To find out how you can benefit from open access to research, see our library web pages and Open Access blog. For open access help contact: openaccess@st-andrews.ac.uk.

Accessibility

Read our Accessibility statement.

How to submit research papers

The full text of research papers can be submitted to the repository via Pure, the University's research information system. For help see our guide: How to deposit in Pure.

Electronic thesis deposit

Help with deposit.

Repository help

For repository help contact: Digital-Repository@st-andrews.ac.uk.

Give Feedback

Cookie policy

This site may use cookies. Please see Terms and Conditions.

Usage statistics

COUNTER-compliant statistics on downloads from the repository are available from the IRUS-UK Service. Contact us for information.

© University of St Andrews Library

University of St Andrews is a charity registered in Scotland, No SC013532.

  • Facebook
  • Twitter