Dataset Information

Global Lysine Crotonylation Alterations of Host Cell Proteins Caused by Brucella GNAT Containing Effector BspF

ABSTRACT: In Brucella spp., the type IV secretion system (T4SS) is essential for bacterial intracellular survival and inhibition of the host innate immune response. The Brucella T4SS secretes 15 different effectors to escape host immunity and promote intracellular replication. Among them, BspF has a GNAT-family acetyltransferase domain, implying its acetyltransferase activity. To test this, in this study, we first tested and confirmed that BspF has de-histone crotonyltransferase activity in vitro. Unexpectedly, we also found that BspF enhances histone crotonylation of host cell proteins. We then conducted enrichment of crotonylated proteins and used LC-MS to study the crotonylation of proteins in HEK-293T cells caused BspF overexpression. A total of 5,559 crotonylation sites were identified on 1,525 different proteins, of which 331 sites on 265 proteins were significantly changed 30 h after transfection. Among these differentially modified proteins, a significant proportions were involved in immune response and defense mechanism. We propose that BspF may influence the function of these host proteins by changing the level of crotonylation, thereby promoting the intracellular propagation of Brucella.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Brucella Sp.

TISSUE(S): Cell Culture

SUBMITTER: Jinying Zhu

LAB HEAD: Zeliang Chen

PROVIDER: PXD021423 | Pride | 2021-09-09

REPOSITORIES: Pride

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Publications

Global Lysine Crotonylation Alterations of Host Cell Proteins Caused by Brucella Effector BspF.

Zhu Jinying J Dong Qiao Q Dong Changpeng C Zhang Xi X Zhang Huan H Chen Zeliang Z

Frontiers in cellular and infection microbiology 20210108

In Brucella spp., the type IV secretion system (T4SS) is essential for bacterial intracellular survival and inhibition of the host innate immune response. The Brucella T4SS secretes 15 different effectors to escape host immunity and promote intracellular replication. Among them, BspF has a GNAT-family acetyltransferase domain, implying its acetyltransferase activity. We confirmed that BspF has acetyltransferase activity (data not shown) and de-crotonyltransferase activity. However, ...[more]

PMID: 33489935

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Dataset Information

Global Lysine Crotonylation Alterations of Host Cell Proteins Caused by Brucella GNAT Containing Effector BspF

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Global Lysine Crotonylation Alterations of Host Cell Proteins Caused by <i>Brucella</i> Effector BspF.

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