A Proteomic View of Salmonella Typhimurium in Response to Phosphate Limitation

Jiezhang Jiang; Kaiwen Yu; Linlu Qi; Yanhua Liu; Sen Cheng; Mei Wu; Zhen Wang; Jiaqi Fu; Xiaoyun Liu

doi:10.3390/proteomes6020019

A Proteomic View of Salmonella Typhimurium in Response to Phosphate Limitation

Proteomes. 2018 Apr 25;6(2):19. doi: 10.3390/proteomes6020019.

Authors

Jiezhang Jiang¹, Kaiwen Yu², Linlu Qi³, Yanhua Liu⁴, Sen Cheng⁵, Mei Wu⁶, Zhen Wang⁷, Jiaqi Fu⁸, Xiaoyun Liu⁹

Affiliations

¹ Institute of Analytical Chemistry and Synthetic and Functional Biomolecules Center, College of Chemistry and Molecular Engineering, Peking University, 202 Chengfu Rd, Haidian District, Beijing 100871, China. jiangjiezhang@pku.edu.cn.
² Institute of Analytical Chemistry and Synthetic and Functional Biomolecules Center, College of Chemistry and Molecular Engineering, Peking University, 202 Chengfu Rd, Haidian District, Beijing 100871, China. kwyu@pku.edu.cn.
³ Institute of Analytical Chemistry and Synthetic and Functional Biomolecules Center, College of Chemistry and Molecular Engineering, Peking University, 202 Chengfu Rd, Haidian District, Beijing 100871, China. qilinlu1987@126.com.
⁴ Institute of Analytical Chemistry and Synthetic and Functional Biomolecules Center, College of Chemistry and Molecular Engineering, Peking University, 202 Chengfu Rd, Haidian District, Beijing 100871, China. liuyanhua@pku.edu.cn.
⁵ Institute of Analytical Chemistry and Synthetic and Functional Biomolecules Center, College of Chemistry and Molecular Engineering, Peking University, 202 Chengfu Rd, Haidian District, Beijing 100871, China. chengsen@pku.edu.cn.
⁶ Institute of Analytical Chemistry and Synthetic and Functional Biomolecules Center, College of Chemistry and Molecular Engineering, Peking University, 202 Chengfu Rd, Haidian District, Beijing 100871, China. wumei@pku.edu.cn.
⁷ Institute of Analytical Chemistry and Synthetic and Functional Biomolecules Center, College of Chemistry and Molecular Engineering, Peking University, 202 Chengfu Rd, Haidian District, Beijing 100871, China. zhenw@pku.edu.cn.
⁸ Institute of Analytical Chemistry and Synthetic and Functional Biomolecules Center, College of Chemistry and Molecular Engineering, Peking University, 202 Chengfu Rd, Haidian District, Beijing 100871, China. fujiaqi@pku.edu.cn.
⁹ Institute of Analytical Chemistry and Synthetic and Functional Biomolecules Center, College of Chemistry and Molecular Engineering, Peking University, 202 Chengfu Rd, Haidian District, Beijing 100871, China. xiaoyun.liu@pku.edu.cn.

Abstract

Salmonella enterica serovar Typhimurium (S. Typhimurium), an important foodborne pathogen, often encounters phosphate (P_i) shortage both in the environment and inside host cells. To gain a global view on its physiological responses to P_i starvation, we performed proteomic profiling of S. Typhimurium upon the shift from P_i-rich to P_i-low conditions. In addition to the Pho regulon, many metabolic processes were up-regulated, such as glycolysis, pentose phosphate pathway, pyrimidine degradation, glycogen, and trehalose metabolism, allowing us to chart an overview of S. Typhimurium carbon metabolism under P_i starvation. Furthermore, proteomic analysis of a mutant lacking phoB (that encodes a key regulator of P_i shortage response) suggested that only a small subset of the altered proteins upon P_i limitation was PhoB-dependent. Importantly, we present evidence that S. Typhimurium N-acetylglucosamine catabolism was induced under P_i-limiting conditions in a PhoB-dependent manner. Immunoblotting and β-galactosidase assays demonstrated that PhoB was required for the full activation of NagB, a key enzyme of this pathway, in response to low P_i. Thus, our study reveals that N-acetylglucosamine catabolism may represent an additional PhoB-regulated pathway to tackle bacterial P_i shortage.

Keywords: Salmonella Typhimurium; phosphate starvation; the PhoR-PhoB two-component system; the nag operon.