Environment-specific virocell metabolic reprogramming

Area of Science:

• Microbial Ecology
• Virology
• Systems Biology

Background:

• Viruses significantly influence microbial ecosystems by affecting host cells, gene transfer, and nutrient cycling.
• Virus-infected cells, termed virocells, exhibit altered metabolism as viruses hijack cellular machinery.
• The metabolic adaptations of virocells under nutrient-limited conditions remain largely unexplored.

Purpose of the Study:

• To investigate the metabolic reprogramming of virocells under nutrient limitation using a systems biology approach.
• To understand how low phosphate conditions impact marine bacterial virocells infected by different phages.
• To identify common and specific metabolic strategies employed by virocells during nutrient stress.

Main Methods:

• Utilized a systems biology approach combining transcriptomics, proteomics, lipidomics, and metabolomics.
• Assessed the impact of low phosphate conditions on marine Pseudoalteromonas host virocells infected by phages HP1 and HS2.
• Analyzed both endo- and exo-metabolites to capture a comprehensive metabolic profile.

Main Results:

• Low phosphate induced common cellular responses, including phosphate stress response activation and reduced organic matter consumption.
• Infection-specific responses to low phosphate included enhanced nitrogen assimilation and altered lipid metabolism.
• Virocells exhibited distinct strategies: HS2-virocells increased transcription and ribosomal production, while HP1-virocells accumulated host proteins and broadened resource acquisition.

Conclusions:

• Environmental conditions impose general metabolic responses on all cells, regardless of viral infection.
• Virocells develop specific metabolic strategies to support viral replication under nutrient limitation.
• A framework is established for studying the metabolic strategies of nutrient-limited virocells in natural environments.