Genomic and transcriptomic analyses reveal distinct biological functions for cold shock proteins (VpaCspA and VpaCspD) in Vibrio parahaemolyticus CHN25 during low-temperature survival

BMC Genomics

Research Article

Xu Peng¹  Qunxin She¹  Taigang Liu²  Yaping Wang³  Chunhua Zhu³  Lanming Chen³  Boyi Sun³  Fengjiao Sun³  Lu Xie⁴  Wei He⁵  Meicheng Yang⁶  Huajun Zheng⁷  Wenyi Gu⁷  Weicheng Bei⁸ 

[1] Archaea Centre, Department of Biology, University of Copenhagen, Ole Maaløes Vej 5, DK2200, Copenhagen N, Denmark;College of Information Technology, Shanghai Ocean University, 999 Hu Cheng Huan Road, 201306, Shanghai, People’s Republic of China;Key Laboratory of Quality and Safety Risk Assessment for Aquatic Products on Storage and Preservation (Shanghai), China Ministry of Agriculture; College of Food Science and Technology, Shanghai Ocean University, 999 Hu Cheng Huan Road, 201306, Shanghai, People’s Republic of China;Shanghai Center for Bioinformation Technology, 1278 Keyuan Road, 201203, Shanghai, People’s Republic of China;Shanghai Hanyu Bio-lab, 151 Ke Yuan Road, 201203, Shanghai, People’s Republic of China;Shanghai Institute for Food and Drug Control, 1500 Zhang Heng Road, 201203, Shanghai, People’s Republic of China;Shanghai-MOST Key Laboratory of Disease and Health Genomics, Chinese National Human Genome Centre at Shanghai, 201203, Shanghai, People’s Republic of China;State Key Laboratory of Agricultural Microbiology, Laboratory of Animal Infectious Diseases, College of Animal Science & Veterinary Medicine, Huazhong Agricultural University, 430070, Wuhan, Hubei, People’s Republic of China;

关键词: Vibrio parahaemolyticus;    Complete genome sequence;    Cold shock protein;    Gene deletion;    Transcriptome;    Low-temperature adaptation;   

DOI  :  10.1186/s12864-017-3784-5

 received in 2016-08-09, accepted in 2017-05-10,  发布年份 2017

来源: Springer

【 摘 要 】

BackgroundVibrio parahaemolyticus causes serious seafood-borne gastroenteritis and death in humans. Raw seafood is often subjected to post-harvest processing and low-temperature storage. To date, very little information is available regarding the biological functions of cold shock proteins (CSPs) in the low-temperature survival of the bacterium. In this study, we determined the complete genome sequence of V. parahaemolyticus CHN25 (serotype: O5:KUT). The two main CSP-encoding genes (VpacspA and VpacspD) were deleted from the bacterial genome, and comparative transcriptomic analysis between the mutant and wild-type strains was performed to dissect the possible molecular mechanisms that underlie low-temperature adaptation by V. parahaemolyticus.ResultsThe 5,443,401-bp V. parahaemolyticus CHN25 genome (45.2% G + C) consisted of two circular chromosomes and three plasmids with 4,724 predicted protein-encoding genes. One dual-gene and two single-gene deletion mutants were generated for VpacspA and VpacspD by homologous recombination. The growth of the ΔVpacspA mutant was strongly inhibited at 10 °C, whereas the VpacspD gene deletion strongly stimulated bacterial growth at this low temperature compared with the wild-type strain. The complementary phenotypes were observed in the reverse mutants (ΔVpacspA-com, and ΔVpacspD-com). The transcriptome data revealed that 12.4% of the expressed genes in V. parahaemolyticus CHN25 were significantly altered in the ΔVpacspA mutant when it was grown at 10 °C. These included genes that were involved in amino acid degradation, secretion systems, sulphur metabolism and glycerophospholipid metabolism along with ATP-binding cassette transporters. However, a low temperature elicited significant expression changes for 10.0% of the genes in the ΔVpacspD mutant, including those involved in the phosphotransferase system and in the metabolism of nitrogen and amino acids. The major metabolic pathways that were altered by the dual-gene deletion mutant (ΔVpacspAD) radically differed from those that were altered by single-gene mutants. Comparison of the transcriptome profiles further revealed numerous differentially expressed genes that were shared among the three mutants and regulators that were specifically, coordinately or antagonistically modulated by VpaCspA and VpaCspD. Our data also revealed several possible molecular coping strategies for low-temperature adaptation by the bacterium.ConclusionsThis study is the first to describe the complete genome sequence of V. parahaemolyticus (serotype: O5:KUT). The gene deletions, complementary insertions, and comparative transcriptomics demonstrate that VpaCspA is a primary CSP in the bacterium, while VpaCspD functions as a growth inhibitor at 10 °C. These results have improved our understanding of the genetic basis for low-temperature survival by the most common seafood-borne pathogen worldwide.

【 授权许可】

CC BY   
© The Author(s). 2017