Umeå University's logo

umu.sePublications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
MacP bypass variants of Streptococcus pneumoniae PBP2a suggest a conserved mechanism for the activation of bifunctional cell wall synthases
Department of Microbiology, Harvard Medical School, Blavatnik Institute, Boston, Massachusetts, USA.
Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine).
Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Blavatnik Institute, Boston, Massachusetts, USA.
Umeå University, Faculty of Medicine, Molecular Infection Medicine Sweden (MIMS). Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine). Umeå University, Faculty of Medicine, Umeå Centre for Microbial Research (UCMR).ORCID iD: 0000-0001-5995-718x
Show others and affiliations
2023 (English)In: mBio, ISSN 2161-2129, E-ISSN 2150-7511, Vol. 14, no 6, article id e0239023Article in journal (Refereed) Published
Abstract [en]

The peptidoglycan (PG) layer protects bacteria from osmotic lysis and defines their shape. The class A penicillin-binding proteins (aPBPs) are PG synthases that possess both glycan polymerization and crosslinking activities needed for PG biogenesis. In Gram-negative bacteria, aPBPs require activation by outer membrane lipoproteins, which are thought to stimulate their cognate synthase by inducing conformational changes that promote polymerase function. How aPBPs are controlled in Gram-positive bacteria is less clear. One of the few known regulators is MacP in Streptococcus pneumoniae (Sp). MacP is required for the activity of Sp PBP2a, but its mode of action has been obscure. We therefore selected for PBP2a variants capable of functioning in the absence of MacP. Amino acid substitutions that bypassed the MacP requirement for PBP2a function in vivo also activated its polymerase activity in vitro. Many of these changes mapped to the interface between the transmembrane (TM) helix and polymerase domain in a model PBP2a structure. This region is conformationally flexible in the experimentally determined structures of aPBPs and undergoes a structural transition upon binding the substrate-mimicking drug moenomycin. Our findings suggest that MacP promotes PG polymerization by altering the TM-polymerase domain interface in PBP2a and that this mechanism for aPBP activation may be broadly conserved. Furthermore, Sp cells expressing an activated PBP2a variant displayed heterogeneous shapes, highlighting the importance of proper aPBP regulation in cell morphogenesis.

Importance: Class A penicillin-binding proteins (aPBPs) play critical roles in bacterial cell wall biogenesis. As the targets of penicillin, they are among the most important drug targets in history. Although the biochemical activities of these enzymes have been well studied, little is known about how they are regulated in cells to control when and where peptidoglycan is made. In this report, we isolate variants of the Streptococcus pneumoniae enzyme PBP2a that function in cells without MacP, a partner normally required for its activity. The amino acid substitutions activate the cell wall synthase activity of PBP2a, and their location in a model structure suggests an activation mechanism for this enzyme that is shared with aPBPs from distantly related organisms with distinct activators.

Place, publisher, year, edition, pages
American Society for Microbiology, 2023. Vol. 14, no 6, article id e0239023
Keywords [en]
penicillin-binding proteins, peptidoglycan, cell envelope, cell wall
National Category
Medical Biotechnology (with a focus on Cell Biology (including Stem Cell Biology), Molecular Biology, Microbiology, Biochemistry or Biopharmacy) Microbiology in the medical area
Identifiers
URN: urn:nbn:se:umu:diva-218565DOI: 10.1128/mbio.02390-23ISI: 001085326900001PubMedID: 37847021Scopus ID: 2-s2.0-85183091235OAI: oai:DiVA.org:umu-218565DiVA, id: diva2:1823799
Funder
Knut and Alice Wallenberg FoundationThe Kempe FoundationsSwedish Research CouncilAvailable from: 2024-01-03 Created: 2024-01-03 Last updated: 2024-02-13Bibliographically approved

Open Access in DiVA

fulltext(1682 kB)39 downloads
File information
File name FULLTEXT01.pdfFile size 1682 kBChecksum SHA-512
0ec6b885aa1e2b2322c8c6b1fe7fce178330d6953137ad9c75025ce1786707fca878f9697e0324258e3e283b3e7c848129547e173b563a5070cadf5b83c8c49f
Type fulltextMimetype application/pdf

Other links

Publisher's full textPubMedScopus

Authority records

Bisset, SeanCava, Felipe

Search in DiVA

By author/editor
Bisset, SeanCava, FelipeRudner, David Z.
By organisation
Department of Molecular Biology (Faculty of Medicine)Molecular Infection Medicine Sweden (MIMS)Umeå Centre for Microbial Research (UCMR)
In the same journal
mBio
Medical Biotechnology (with a focus on Cell Biology (including Stem Cell Biology), Molecular Biology, Microbiology, Biochemistry or Biopharmacy)Microbiology in the medical area

Search outside of DiVA

GoogleGoogle Scholar
Total: 39 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

doi
pubmed
urn-nbn

Altmetric score

doi
pubmed
urn-nbn
Total: 202 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf