Project description:Pectobacterium are Gram-negative rods of the family Pectobacteriaceae. They are the causative agent of soft rot diseases of crops and ornamental plants. However, their virulence mechanisms are not yet fully elucidated. Membrane vesicles (MVs) are universally released by bacteria and are be-lieved to play an important role in pathogenicity, and survival of bacteria in the environment. Our study investigates the role of MVs in the virulence of Pectobacterium. The results indicate that the morphology and yields of MVs depend on medium composition. In polygalacturonic acid (PGA) supplemented media, Pectobacterium produce MVs of a larger size (100-300 nm) apart of vesicles below 100 nm. Proteomic analyses revealed the presence of pectate degrading enzymes in MVs. The pectate plate test and enzymatic assay proved that those enzymes are active and able to de-grade pectates. What is more, pathogenicity test indicated that MVs derived from Pectobacterium were able to induce maceration of Zantedeschia sp. leaves. We also show that MVs of β-lactamase producing strains were able to suppress ampicillin activity and permit the growth of susceptible bacteria. Those findings indicate that MVs of Pectobacterium play an important role in host-pathogen interactions and niche competition with other bacteria. Our research also sheds some light on the mechanism of MVs production. We demonstrate that Pectobacterium strains, which overexpress the green fluorescence protein (GFP), produce more MVs than wild type strains. Moreover, proteomic analysis revealed that GFP was present in MVs. Therefore, we demonstrate that protein sequestration into MVs is not limited strictly to periplasmic proteins and is a common occurrence. Our research highlights the importance of MVs production as a mechanism of cargo delivery in Pectobacterium and an alternative secretion system.

2022-02-15 | PXD029090 | Pride

Rhodoblastus acidophilus strain:PC2

Project description:Rhodoblastus strain PC2

| PRJNA752515 | ENA

Maintenance of nucleolar homeostasis by PC2 alleviates senescence and osteoarthritis

Project description:Polycomb 2 protein (PC2), a component of polycomb repressive complex 1 (PRC1), plays important roles in the maintenance of cell identity and organ development through epigenetic silencing. However, whether PC2 regulates the homeostasis of human stem cells remains unclear. Here, we demonstrate that PC2 counteracts human mesenchymal stem cell (hMSC) aging via the maintenance of nucleolar homeostasis. PC2 protein is decreased in aged hMSCs, and targeted PC2 knockout in young hMSCs results in destabilized nucleolar heterochromatin, increased ribosome biogenesis and protein translation, and accelerated cellular senescence. PC2 maintains nucleolar homeostasis by recruiting nucleolar protein fibrillarin and heterochromatin organization associated protein KAP1 at nucleolar rDNA, limiting the excessive expression of rRNAs. Importantly, overexpression of PC2 alleviates physiological hMSC aging and attenuates the development of posttraumatic osteoarthritis in mice. Taken together, our findings reveal a novel role of PC2 in counteracting senescence by maintaining nucleolar homeostasis, providing a potential therapeutic target for aging-associated disorders.

2018-10-10 | GSE121033 | GEO

Transcriptome analysis of Pectobacterium atrosepticum

Project description:The goals of this study are to compare NGS-derived transcriptome profiling (RNA-seq) of Pectobacterium upon treatment of polyphenol compound.

2022-10-05 | GSE196675 | GEO

Transcriptome microarray of wildtype, relA, expI and rpoS Pectobacterium atrosepticum strains in PMB media

Project description:Whole genome analysis of gene expression by Pectobacterium atrosepticum strain SCRI1043 wildtype and its relA, expI and rpoS deletion mutants when grown to exponential and stationary phase in PMB media. The data is further described in Bowden et al (2013) Virulence in Pectobacterium atrosepticum is regulated by a coincidence circuit involving quorum sensing and the stress alarmone, (p)ppGpp. Molecular Microbiology. DOI: 10.1111/mmi.12369

2013-08-30 | GSE50468 | GEO

Pectobacterium zantedeschiae

Project description:Pectobacterium zantedeschiae overview

| PRJNA561876 | ENA