Morphology and distribution of phage-like particles in a eutrophic boreal lagoon*

In this paper we present the results of direct observations of the morphology and size of phage-like particles by means of transmission electron microscopy (TEM) as a function of their spatial distribution in the shallow highly productive Curonian Lagoon of the Baltic Sea. In total, 26 morphologically different forms of phagelike particles were found. Different trends of distribution in terms of abundance, size and shape of virus-like particles were demonstrated. The total abundance of viruses varied from 1.91×107 ml−1 to 5.06×107 ml−1. The virus to bacteria ratio (VBR) changed from 15.6 to 49 and was negatively associated with total bacterial numbers (r = –0.60; p < 0.05). The phages of family Myoviridae were the most diverse and were dominant at all stations.