Journal Article

Characterization of a Novel Tectivirus Phage Toil and Its Potential as an Agent for Biolipid Extraction

Sestak, Emily, Wang, Baixin, Young, Ryland, Gill, Jason J., Chu, Kung-Hui

2018

Overview

The oleaginous bacterium Rhodococcus opacus PD630 is metabolically diverse and can be cultivated on various renewable resources to serve as a sustainable triacylglycerol (TAG) feedstock for biodiesel production. Current methods for TAG extraction are costly, but infection of cultures by lytic bacteriophages (phages) may be a viable approach for achieving release of intracellular lipid from oleaginous bacteria such as R. opacus . This study reports the novel tectiviral phage Toil capable of releasing intracellular contents including a fluorescent protein marker and TAGs into the supernatant after phage infection of R. opacus PD631, a domesticated derivative of strain PD630. Phage Toil is placed in the Tectiviridae by its morphology, the presence of a lipid membrane, its genome architecture and the presence of terminal covalently-linked proteins. Toil is the first tectivirus capable of infecting a member of the Actinobacteria . Microscopy shows that infected cells do not undergo sudden lysis but instead maintain their original shape for several hours, with the cellular morphology gradually deteriorating. Approximately 30% of intracellular TAGs could be recovered from the culture supernatants of Toil-infected PD631 cells. Phage Toil has potential to be used as an agent in extraction of TAGs from oleaginous bacterium R. opacus . Importance : This study reported the first tectivirus (Phage Toil) capable of infecting a member of the Actinobacteria . In this study, we showed that Phage Toil can infect oleaginous bacterium Rhodococcus opacus to release intracellular contents such as a fluorescent protein marker and TAG lipid granules, which can serve as a starting material for biodiesel production. This study demonstrates a new method to extract TAGs by using this phage. Additionally, Phage Toil can be a new model phage to advance knowledge regarding phage infection mechanisms in Rhodococcus and other mycolic acid-containing bacteria such as Mycobacterium .

• Publisher: Nature Publishing Group UK,Nature Publishing Group
• Subject: 45/23 / 45/77 / 631/208/325/2483 / 631/326/1321 / 631/61/168 / 96/35 / Actinobacteria / Bacteria / Bacteria - metabolism / Bacteria - virology / Bacteriolysis / Biodiesel fuels / Biofuels / Cell culture / Chemical Fractionation / Diesel / Genome, Viral / Genomes / Genomics - methods / Humanities and Social Sciences / Infections / Intracellular / Lipid Metabolism / Lipids / Lipids - chemistry / Lysis / Morphology / multidisciplinary / Phages / Renewable resources / Rhodococcus opacus / Science / Science (multidisciplinary) / Sustainable yield / Tectiviridae / Tectiviridae - isolation & purification / Tectiviridae - physiology / Tectiviridae - ultrastructure / Virus Replication