No abstract

In extracts of the unicellular cyanobacterium Gloeothece, the Fe-protein of nitrogenase can be separated by SDS-PAGE into two antigenically identifiable components. Unlike the situation in photosynthetic bacteria such as Rhodospirillum rubrum, these two forms do not arise from covalent modification of the protein by ADP-ribosylation. Rather, the Fe-protein of Gloeothece nitrogenase is subjected to modification by palmitoylation.

When grown aerobically under alternating 12 h light and 12 h darkness, the unicellular cyanobacterium Gloeothece fixes N2 only (luring the dark period [ 1.21 In parallel w t h this, immunologically detectable nitrogenase is present only during the last 2 h of the light phase and throughout the dark phase [3]Gallon, J R ( 1 98 1 ) Trends