TABLE 2.

Presence of nitrogen metabolism-related genes in the genomes of Prochlorococcus strains MED4, MIT9313, and SS120 and Synechococcus strain WH8102

Gene(s)Protein(s)Presencea in strain:
MED4MIT9313SS120WH8102
nif clusterNitrogenase and cofactors
narB Nitrate reductase+
nirA Nitrite reductase++
glnA Glutamine synthetase++++
gdhA Glutamate dehydrogenase+
glsF Fd-glutamate synthase++++
ure clusterUrease and cofactors+++
amt1 Ammonium transporter++++
Amino acid transporters+++
Oligopeptide transporters++++
cynABD Cyanate transporter++
cynS Cyanate lyase++
  • a +, present; −, absent.