Production and assembly of stable proheads is an essential precursor to bacteriophage genome packaging; this packaging activity can be replicated in vitro.

The rise of a burgher class to counterbalance the power of the state was the essential precursor to freedom.

His own writings and inspirations make him an essential precursor of this literary movement.

ESP is subsequently dephosphorylated to chorismate, an essential precursor for the amino acids mentioned above.

Cyanide is a deadly poison to animals, but it was an essential precursor to many of the molecules from which primitive life arose.

Johnson's work, allied to the Jamaican "toasting" tradition, is regarded as an essential precursor of rap.

Greigite is considered an essential precursor of framboidal pyrite formation.

His work is recognized today as an essential precursor to contemporary sampling practices.

Mr. Rotberg is entitled to say that "Rhodes' legislative victories in the early 1890s proved essential precursors to apartheid."

The H antigen is an essential precursor to the ABO blood group antigens.