PXD032013

PXD032013 is an original dataset announced via ProteomeXchange.

Title	Sas20 is a highly flexible starch-binding protein in the Ruminococcus bromii cell-surface amylosome
Description	Ruminococcus bromii is a keystone species in the human gut that has the rare ability to degrade dietary resistant starch (RS). This bacterium secretes a suite of starch-active proteins that work together within larger complexes called amylosomes that allow R. bromii to adhere to and degrade RS. Sas20 is one of the more abundant proteins assembled within amylosomes, but little could be predicted about its molecular features based upon amino acid sequence. Here, we perform a structure-function analysis of Sas20 which features two discrete starch-binding domains separated by a flexible linker. Sas20 domain 1 has an N-terminal β-sandwich followed by a cluster of α-helices and captures the non-reducing end of maltooligosaccharides between these structural features. The crystal structure of a close homolog of Sas20 domain 2 revealed a unique bilobed starch-binding groove that targets the helical 1,4-linked glycan chains found in amorphous regions of amylopectin and crystalline regions of amylose within starch granules. Affinity PAGE and isothermal titration calorimetry demonstrate both domains bind maltoheptaose and soluble starch with relatively high affinity (Kd  20 M) but exhibit limited or no binding to cyclodextrins. Small angle x-ray scattering analysis of the individual and combined domains support that these structures are highly flexible, which may allow the protein to adopt conformations that enhance its starch-targeting efficiency.
HostingRepository	PRIDE
AnnounceDate	2022-06-09
AnnouncementXML	Submission_2022-06-09_02:03:09.953.xml
DigitalObjectIdentifier
ReviewLevel	Peer-reviewed dataset
DatasetOrigin	Original dataset
RepositorySupport	Unsupported dataset by repository
PrimarySubmitter	Filipe Cerqueira
SpeciesList	scientific name: Ruminococcus bromii L2-63; NCBI TaxID: 657321;
ModificationList	monohydroxylated residue; iodoacetamide derivatized residue; deamidated residue
Instrument	Orbitrap Fusion

Revision	Datetime	Status	ChangeLog Entry
0	2022-03-02 09:52:28	ID requested
⏵ 1	2022-06-09 02:03:10	announced

Cerqueira FM, Photenhauer AL, Doden HL, Brown AN, Abdel-Hamid AM, Mora, ï, s S, Bayer EA, Wawrzak Z, Cann I, Ridlon JM, Hopkins JB, Koropatkin NM, Sas20 is a highly flexible starch-binding protein in the Ruminococcus bromii cell-surface amylosome. J Biol Chem, 298(5):101896(2022) [pubmed]

submitter keyword: R. bromii

Nicole Koropatkin
contact affiliation	University of Michigan
contact email	nkoropat@umich.edu
lab head
Filipe Cerqueira
contact affiliation	University of Michigan
contact email	filipehu@umich.edu
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/2022/06/PXD032013

PRIDE project URI

• PRIDE
  1. PXD032013
     1. Label: PRIDE project
     2. Name: Sas20 is a highly flexible starch-binding protein in the Ruminococcus bromii cell-surface amylosome