Journal Article

Differential impact of lytic viruses on prokaryotic morphopopulations in a tropical estuarine system (Cochin estuary, India)

Jasna, Vijayan, Pradeep Ram, Angia Sriram, Parvathi, Ammini, Sime-Ngando, Telesphore

2018

Overview

Our understanding on the importance of viral lysis in the functioning of tropical estuarine ecosystem is limited. This study examines viral infection of prokaryotes and subsequent lysis of cells belonging to different morphotypes across a salinity gradient in monsoon driven estuarine ecosystem (Cochin estuary, India). High standing stock of viruses and prokaryotes accompanied by lytic infection rates in the euryhaline/mesohaline region of the estuary suggests salinity to have an influential role in driving interactions between prokaryotes and viruses. High prokaryotic mortality rates, up to 42% of prokaryote population in the pre-monsoon season is further substantiated by a high virus to prokaryote ratio (VPR), suggesting that maintenance of a high number of viruses is dependent on the most active fraction of bacterioplankton. Although myoviruses were the dominant viral morphotype (mean = 43%) throughout the study period, there was significant variation among prokaryotic morphotypes susceptible to viral infection. Among them, the viral infected short rod prokaryote morphotype with lower burst estimates (mean = 18 viruses prokaryote-1) was dominant (35%) in the dry seasons whereas a substantial increase in cocci forms (30%) infected by viruses with high burst size (mean = 31 viruses prokaryote-1) was evident during the monsoon season. Such preferential infections of prokaryotic morphopopulations with respect to seasons can have a strong and variable impact on the carbon and energy flow in this tropical ecosystem.

• Publisher: Public Library of Science,Public Library of Science (PLoS)
• Subject: Bacteria - virology / Bacteriology / Bacterioplankton / Biology and Life Sciences / Burst size / Carbon / Coasts / Cocci / Dry season / Earth Sciences / Ecological research / Ecosystem / Ecosystems / Energy flow / Environmental aspects / Environmental Monitoring - methods / Estuaries / Estuarine ecosystems / Estuarine environments / Fresh Water - virology / Health aspects / India / Infections / Life Sciences / Lysis / Marine ecology / Microbiology and Parasitology / Monsoons / Mortality / Nitrates / Oceanography / Physical Sciences / Prokaryotes / Prokaryotic Cells - virology / Protistology / Salinity / Salinity effects / Salinity gradients / Seasons / Sediments / Viral infections / Virology / Virus diseases / Virus Diseases - pathology / Virus Diseases - physiopathology / Virus Physiological Phenomena / Viruses / Vpr protein / Wind