title: ULTRASTRUCTURAL CHARACTERIZATION OF THE LYTIC CYCLE OF AN INTRANUCLEAR VIRUS INFECTING THE DIATOM CHAETOCEROS CF. WIGHAMII(BACILLARIOPHYCEAE) FROM CHESAPEAKE BAY, USA(1).
abstract: Numerous microalgal species are infected by viruses that have the potential to control phytoplankton dynamics by reducing host populations, preventing bloom formation, or causing the collapse of blooms. Here we describe a virus infecting the diatom Chaetoceros cf. wighamii Brightw. from the Chesapeake Bay. To characterize the morphology and lytic cycle of this virus, we conducted a time-course experiment, sampling every 4 h over 72 h following viral inoculation. In vivo fluorescence began to decline 16 h after inoculation and was reduced to <19% of control cultures by the end of experiment. TEM confirmed infection within the first 8 h of inoculation, as indicated by the presence of virus-like particles (VLP) in the nuclei. VLP were present in two different arrangements: rod-like structures that appeared in cross-section as paracrystalline arrays of hexagonal-shaped profiles measuring 12 ± 2 nm in diameter and uniformly electron-dense hexagonal-shaped particles measuring ∼ 22-28 nm in diameter. Nuclei containing paracrystalline arrays were most prevalent early in the infection cycle, while cells containing VLP increased and then declined toward the end of the cycle. The proportion of nuclei containing both paracrystalline arrays and VLP remained relatively constant. This pattern suggests that rod-like paracrystalline arrays fragmented to produce icosahedral VLP. C. cf. wighamii nuclear inclusion virus (CwNIV) is characterized by a high burst size (averaged 26,400 viruses per infected cell) and fast generation time that could have ecological implications on C. cf. wighamii population control.
authors.affiliation: Centro de Investigación y Gestión de Recursos Naturales, Departamento de Química y Bioquímica, Facultad de Ciencias, Universidad de Valparaíso, Gran Bretaña 1111, Playa Ancha, Valparaíso, Chile CIEN Austral, Universidad Austral de Chile, Los Pinos S/N, Balneario Pelluco, Casilla 1327, Puerto Montt, ChileCenter of Marine Biotechnology, University of Maryland, 701 East Pratt Street, Baltimore, Maryland 21202, USADelaware Biotechnology Institute, 15 Innovation Way, Newark, Delaware 19711, USASmithsonian Environmental Research Center, 647 Contees Wharf Road, Edgewater, Maryland 21037, USA.
authors.forename: Yoanna
authors.initials: Y
authors.lastname: Eissler
authors.affiliation: Centro de Investigación y Gestión de Recursos Naturales, Departamento de Química y Bioquímica, Facultad de Ciencias, Universidad de Valparaíso, Gran Bretaña 1111, Playa Ancha, Valparaíso, Chile CIEN Austral, Universidad Austral de Chile, Los Pinos S/N, Balneario Pelluco, Casilla 1327, Puerto Montt, ChileCenter of Marine Biotechnology, University of Maryland, 701 East Pratt Street, Baltimore, Maryland 21202, USADelaware Biotechnology Institute, 15 Innovation Way, Newark, Delaware 19711, USASmithsonian Environmental Research Center, 647 Contees Wharf Road, Edgewater, Maryland 21037, USA.
authors.forename: Kui
authors.initials: K
authors.lastname: Wang
authors.affiliation: Centro de Investigación y Gestión de Recursos Naturales, Departamento de Química y Bioquímica, Facultad de Ciencias, Universidad de Valparaíso, Gran Bretaña 1111, Playa Ancha, Valparaíso, Chile CIEN Austral, Universidad Austral de Chile, Los Pinos S/N, Balneario Pelluco, Casilla 1327, Puerto Montt, ChileCenter of Marine Biotechnology, University of Maryland, 701 East Pratt Street, Baltimore, Maryland 21202, USADelaware Biotechnology Institute, 15 Innovation Way, Newark, Delaware 19711, USASmithsonian Environmental Research Center, 647 Contees Wharf Road, Edgewater, Maryland 21037, USA.
authors.forename: Feng
authors.initials: F
authors.lastname: Chen
authors.affiliation: Centro de Investigación y Gestión de Recursos Naturales, Departamento de Química y Bioquímica, Facultad de Ciencias, Universidad de Valparaíso, Gran Bretaña 1111, Playa Ancha, Valparaíso, Chile CIEN Austral, Universidad Austral de Chile, Los Pinos S/N, Balneario Pelluco, Casilla 1327, Puerto Montt, ChileCenter of Marine Biotechnology, University of Maryland, 701 East Pratt Street, Baltimore, Maryland 21202, USADelaware Biotechnology Institute, 15 Innovation Way, Newark, Delaware 19711, USASmithsonian Environmental Research Center, 647 Contees Wharf Road, Edgewater, Maryland 21037, USA.
authors.forename: K
authors.initials: K
authors.lastname: Eric Wommack
authors.affiliation: Centro de Investigación y Gestión de Recursos Naturales, Departamento de Química y Bioquímica, Facultad de Ciencias, Universidad de Valparaíso, Gran Bretaña 1111, Playa Ancha, Valparaíso, Chile CIEN Austral, Universidad Austral de Chile, Los Pinos S/N, Balneario Pelluco, Casilla 1327, Puerto Montt, ChileCenter of Marine Biotechnology, University of Maryland, 701 East Pratt Street, Baltimore, Maryland 21202, USADelaware Biotechnology Institute, 15 Innovation Way, Newark, Delaware 19711, USASmithsonian Environmental Research Center, 647 Contees Wharf Road, Edgewater, Maryland 21037, USA.
authors.forename: D
authors.initials: D
authors.lastname: Wayne Coats
keywords: Chaetoceros; algal virus; diatom; viral ecology; virus