Bifunctional aspartokinase I/homeserine dehydrogenase I; In the C-terminal section; belongs to the homoserine dehydrogenase family.

Translation initiation factor IF-1; One of the essential components for the initiation of protein synthesis. Stabilizes the binding of IF-2 and IF-3 on the 30S subunit to which N-formylmethionyl-tRNA(fMet) subsequently binds. Helps modulate mRNA selection, yielding the 30S pre-initiation complex (PIC). Upon addition of the 50S ribosomal subunit IF-1, IF-2 and IF-3 are released leaving the mature 70S translation initiation complex.

Biotin--protein ligase; Acts both as a biotin--[acetyl-CoA-carboxylase] ligase and a biotin-operon repressor. In the presence of ATP, BirA activates biotin to form the BirA-biotinyl-5'-adenylate (BirA-bio-5'-AMP or holoBirA) complex. HoloBirA can either transfer the biotinyl moiety to the biotin carboxyl carrier protein (BCCP) subunit of acetyl-CoA carboxylase, or bind to the biotin operator site and inhibit transcription of the operon.

4-hydroxythreonine-4-phosphate dehydrogenase; Catalyzes the NAD(P)-dependent oxidation of 4-(phosphooxy)-L- threonine (HTP) into 2-amino-3-oxo-4-(phosphooxy)butyric acid which spontaneously decarboxylates to form 3-amino-2-oxopropyl phosphate (AHAP).

Uroporphyrinogen-III C-methyltransferase; Multifunctional enzyme that catalyzes the SAM-dependent methylations of uroporphyrinogen III at position C-2 and C-7 to form precorrin-2 via precorrin-1. Then it catalyzes the NAD-dependent ring dehydrogenation of precorrin-2 to yield sirohydrochlorin. Finally, it catalyzes the ferrochelation of sirohydrochlorin to yield siroheme. Belongs to the precorrin methyltransferase family. In the N-terminal section; belongs to the precorrin-2 dehydrogenase / sirohydrochlorin ferrochelatase family.

Dimethyladenosine transferase; Specifically dimethylates two adjacent adenosines (A1518 and A1519) in the loop of a conserved hairpin near the 3'-end of 16S rRNA in the 30S particle. May play a critical role in biogenesis of 30S subunits.