Continuous Assembly of beta-Roll Structures Is Implicated in the Type I-Dependent Secretion of Large Repeat-in-Toxins (RTX) Proteins

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61388971%3A_____%2F20%3A00533857" target="_blank" >RIV/61388971:_____/20:00533857 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/00216208:11310/20:10421603

Výsledek na webu

<a href="https://www.sciencedirect.com/science/article/pii/S0022283620305143" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0022283620305143</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.jmb.2020.08.020" target="_blank" >10.1016/j.jmb.2020.08.020</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Continuous Assembly of beta-Roll Structures Is Implicated in the Type I-Dependent Secretion of Large Repeat-in-Toxins (RTX) Proteins

Popis výsledku v původním jazyce

Repeats-in-Toxin (RTX) proteins of Gram-negative bacteria are excreted through the type I secretion system (T1SS) that recognizes non-cleavable C-terminal secretion signals. These are preceded by arrays of glycine and aspartate-rich nonapeptide repeats grouped by four to eight beta strands into blocks that fold into calcium binding parallel beta-roll structures. The beta-rolls are interspersed by linkers of variable length and sequence and the organization of multiple RTX repeat blocks within large RTX domains remains unknown. Here we examined the structure and function of the RTX domain of Bordetella pertussis adenylate cyclase toxin (CyaA) that is composed of five 6-roll RTX blocks. We show that the non-folded RTX repeats maintain the stability of the CyaA polypeptide in the Ca2+-depleted bacterial cytosol and thereby enable its efficient translocation through the Ti SS apparatus. The efficacy of secretion of truncated CyaA constructs was dictated by the number of retained RTX repeat blocks and depended on the presence of extracellular Ca2+ ions. We further describe the crystal structure of the RTX blocks IV-V of CyaA (CyaA(1372-1681)) that consists of a contiguous assembly of two beta-rolls that differs substantially from the arrangement of the RTX blocks observed in RTX lipases or other RTX proteins. These results provide a novel structural insight into the architecture of the RTX domains of large RTX proteins and support the ´push-ratchet´mechanism of the T1SS-mediated secretion of very large RTX proteins.

Název v anglickém jazyce

Continuous Assembly of beta-Roll Structures Is Implicated in the Type I-Dependent Secretion of Large Repeat-in-Toxins (RTX) Proteins

Popis výsledku anglicky

Repeats-in-Toxin (RTX) proteins of Gram-negative bacteria are excreted through the type I secretion system (T1SS) that recognizes non-cleavable C-terminal secretion signals. These are preceded by arrays of glycine and aspartate-rich nonapeptide repeats grouped by four to eight beta strands into blocks that fold into calcium binding parallel beta-roll structures. The beta-rolls are interspersed by linkers of variable length and sequence and the organization of multiple RTX repeat blocks within large RTX domains remains unknown. Here we examined the structure and function of the RTX domain of Bordetella pertussis adenylate cyclase toxin (CyaA) that is composed of five 6-roll RTX blocks. We show that the non-folded RTX repeats maintain the stability of the CyaA polypeptide in the Ca2+-depleted bacterial cytosol and thereby enable its efficient translocation through the Ti SS apparatus. The efficacy of secretion of truncated CyaA constructs was dictated by the number of retained RTX repeat blocks and depended on the presence of extracellular Ca2+ ions. We further describe the crystal structure of the RTX blocks IV-V of CyaA (CyaA(1372-1681)) that consists of a contiguous assembly of two beta-rolls that differs substantially from the arrangement of the RTX blocks observed in RTX lipases or other RTX proteins. These results provide a novel structural insight into the architecture of the RTX domains of large RTX proteins and support the ´push-ratchet´mechanism of the T1SS-mediated secretion of very large RTX proteins.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10606 - Microbiology

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2020

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of Molecular Biology

ISSN

0022-2836

e-ISSN

—

Svazek periodika

432

Číslo periodika v rámci svazku

20

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

15

Strana od-do

5696-5710

Kód UT WoS článku

000576472300012

EID výsledku v databázi Scopus

2-s2.0-85090483661