Abstract:
Viruses are the numerically most abundant biological entities on Earth. The lecture will review approaches for studying the human-associated virome. The lecture will overview results from the field, then focus on two recent studies. The first characterizes the mechanism of colonization of human neonates by viruses. Neonates begin life sterile, but by one month virus-like particles are detectable in stool at a billion per gram. Multiple research strategies show that prophage induction provides a first wave of viral colonization. Viruses that grow on human cells appear later, and abundance of these viruses are negatively associated with breast feeding. Thus colonization of the gut of neonates appears to be step-wise, first by prophages induced from pioneer bacteria, and secondly by viruses infecting human cells, which is inhibited by breastfeeding. The second reports on studies of the virome dark matter, and the identification a new family of human-associated oro respiratory viruses recovered from the viral dark matter, named Redondoviruses.