PXD074249

PXD074249 is an original dataset announced via ProteomeXchange.

Title	Activation-independent capture of free fatty acids at the cell envelope by BrtB
Description	Fatty acids (FAs) are central to cyanobacterial physiology, shaping membrane architecture and cellular acclimatization. Because most cyanobacteria lack β-oxidation, FA fate relies on alternative pathways, including FA-derived natural products whose physiological roles remain poorly defined. Here we show that in the cyanobacterium Synechocystis salina LEGE 06099, the enzyme BrtB catalyzes the activation-independent esterification of free FAs onto the abundant secondary metabolites bartolosides, at the cell envelope, generating bartoloside fatty acid esters (B-FAs). Using stable isotope labeled FA supplementation, RNA-seq, and proteomic analyses, we find that upon exogenous FA feeding, the cellular composition of bartoloside-related metabolites change within minutes while the transcriptome and exoproteome remains unchanged. With increasing concentrations of supplied FAs, B-FA levels reach a plateau whereas bartolosides decrease and hydroxy bartolosides increase, consistent with a rapid ester hydrolysis cycle. BrtB is present at the cell envelope, and its secreted levels are not induced by FA addition, indicating a pre-positioned, envelope enzyme. Together, these results define an activation-independent FA capture pathway at the cell envelope supporting a model in which the brt system transiently sequesters free FAs to establish a steady B-FA pool while re-routing excess to membrane lipids.
HostingRepository	PRIDE
AnnounceDate	2026-08-20
AnnouncementXML	Submission_2026-08-20_04:08:26.873.xml
DigitalObjectIdentifier
ReviewLevel	Peer-reviewed dataset
DatasetOrigin	Original dataset
RepositorySupport	Unsupported dataset by repository
PrimarySubmitter	David A. Russo
SpeciesList	scientific name: Synechocystis salina LEGE 06099; NCBI TaxID: NEWT:945781;
ModificationList	No PTMs are included in the dataset
Instrument	timsTOF HT

Revision	Datetime	Status	ChangeLog Entry
0	2026-02-09 12:27:25	ID requested
⏵ 1	2026-08-20 04:08:27	announced

10.1128/MBIO.01132-26;

submitter keyword: Synechocystis salina LEGE 06099, LC-MS, exoproteomics

David A. Russo
contact affiliation	Friedrich Schiller University Jena
contact email	david.russo@uni-jena.de
lab head
David A. Russo
contact affiliation	Friedrich Schiller University Jena
contact email	david.russo@uni-jena.de
dataset submitter

Dataset FTP location NOTE: Most web browsers have now discontinued native support for FTP access within the browser window. But you can usually install another FTP app (we recommend FileZilla) and configure your browser to launch the external application when you click on this FTP link. Or otherwise, launch an app that supports FTP (like FileZilla) and use this address: ftp://ftp.pride.ebi.ac.uk/pride/data/archive/2026/08/PXD074249

PRIDE project URI

• PRIDE
  1. PXD074249
     1. Label: PRIDE project
     2. Name: Activation-independent capture of free fatty acids at the cell envelope by BrtB