Escherichia coli nfuA is essential for maintenance of Shiga toxin phage Min27 lysogeny under iron-depleted condition.
It has been earlier hypothesized that lysogenic infection with Stx-encoding phages influences protein expression in the bacterial host, and therefore, some differentially expressed proteins could affect survival characteristics and pathogenicity. We compared the protein expression profiles of the host MG1655 and lysogens by 2D electrophoresis. Four different genes identified were all related to Fe/S subunit production, namely, nfuA, fdoH, sdhB and ftnA. To explore the role of nfuA in the biology of Stx prophage lysogeny, gene knockout experiments and phage lysogenic conversion were performed. The inactivation of nfuA caused the prophage to enter its lytic life cycle, especially under an iron-depleted condition. A similar activity was also detected in the Escherichia coli O157:H7 strain from which the Stx phage Min 27 was originally isolated. NfuA might be the positive regulator of genes controlling lysogenic cycle such as cI, cII and cIII since their transcriptional level was significantly reduced in nfuA deletion mutant as shown by qRT-PCR. We conclude that NfuA is essential for maintenance of Stx phage lysogeny in host's genetic reservoir under iron-deficient condition.
Shanghai Key Laboratory of Veterinary Biotechnology, School of Agriculture and Biology, Shanghai Jiaotong University, Shanghai 200240, China;
Dongmei
D
Cao
Shanghai Key Laboratory of Veterinary Biotechnology, School of Agriculture and Biology, Shanghai Jiaotong University, Shanghai 200240, China;
Wenhui
W
Ji
Shanghai Key Laboratory of Veterinary Biotechnology, School of Agriculture and Biology, Shanghai Jiaotong University, Shanghai 200240, China;
Qiang
Q
Fu
Key Laboratory of Animal Disease Diagnosis and Immunology of Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095, Jiangsu Province, China.
Chenping
C
Lu
Shanghai Key Laboratory of Veterinary Biotechnology, School of Agriculture and Biology, Shanghai Jiaotong University, Shanghai 200240, China;
Hengan
H
Wang
Shanghai Key Laboratory of Veterinary Biotechnology, School of Agriculture and Biology, Shanghai Jiaotong University, Shanghai 200240, China;
Jianhe
J
Sun
Shanghai Key Laboratory of Veterinary Biotechnology, School of Agriculture and Biology, Shanghai Jiaotong University, Shanghai 200240, China; yanyaxian@sjtu.edu.cn.
Yaxian
Y
Yan
D003090:Coliphages / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D015180:Electrophoresis, Gel, Two-Dimensional; D019453:Escherichia coli O157 / Q000235:genetics*; D029968:Escherichia coli Proteins / Q000235:genetics* / Q000502:physiology*; D005293:Ferritins / Q000235:genetics; D055786:Gene Knockout Techniques; D007501:Iron / Q000378:metabolism; D000090463:Iron Deficiencies; D007506:Iron-Sulfur Proteins / Q000235:genetics* / Q000502:physiology*; D008242:Lysogeny; D017902:Podoviridae / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D039002:Prophages / Q000235:genetics; D040901:Proteomics; D017384:Sequence Deletion; D022621:Shiga Toxin / Q000235:genetics; D022641:Shiga Toxin 2 / Q000235:genetics
D029968:Escherichia coli Proteins; D007506:Iron-Sulfur Proteins; C529800:NfuA protein, E coli; D022641:Shiga Toxin 2; C534454:ferritin A, E coli; D022621:Shiga Toxin; D005293:Ferritins; D007501:Iron
2D electrophoresis; O157:H7; Stx phage; iron starvation; lysogeny; nfuA