Fig. 1.
The nos cluster of P. stutzeri and its refactoring for recombinant production in E. coli. (A) In the nos cluster of P. stutzeri ZoBell, nosR encodes an integral membrane protein required for electron delivery and function, nosZ is the structural gene for N2O reductase. The ABC transporter complex NosDFY is required for sulfur delivery and NosL is a copper chaperone, and the tatE gene supports Tat-dependent export of apo-NosZ. (B) The protein products of the nos cluster comprise a functional system arranges around the cytoplasmic membrane, with N2O reductase located in the periplasm. In addition to the genes encoded in the cluster, the maturation of NosR additionally requires the flavinyltransferase AbpE that is present in some orthologous gene clusters as nosX. (C) Architecture of the construct pLZPs1containing two synthetic operons for nosRZLtatE and for abpE. The native promoter for NosR was removed for joint transcription, but the original ribosome binding sites for nosZ, nosL, and tatE were retained. (D) Construct pLZPs2 exclusively comprises the NosDFY complex required for sulfur delivery during CuZ maturation. Symbols in C and D are according to Synthetic Biology Open (http://sbolstandard.org).