FUNCTION OF INDIVIDUAL ESCHERICHIA-COLI 30S RIBOSOMAL-PROTEINS AS DETERMINED BY INSITU IMMUNOSPECIFIC NEUTRALIZATION - TENTATIVE CLASSIFICATION

The accessibility of each 30S subunit protein to their cognate antibodies (IgG or Fabs) having been previously well established, the effects of their in situ specific neutralization by monovalent IgG fragments (FabI) are reported for five reactions:o1)T4 and R17 RNA directed protein synthesis;2)polyphenylalanine synthesis;3)enzymatic Phe-tRNA binding in the presence of 30S + 50S subunits;4)fMet-tRNAf binding to the 30S subunit in the presence of initiation factors IF1, IF2, IF3;5)coupling with λplac DNA transcription of the initial translation step (i.e., interaction of IF3 activated 30S subunits with nascent mRNA, in the absence of tRNA). According to evident similarities in their inhibition pattern concerning the five reactions tested, 30S subunit proteins can be classified in five categories which are discussed in terms of functional topography. © 1979 Masson, Paris.