Maize chloroplast DNA encodes a protein sequence homologous to the bacterial ribosome assembly protein S4

Abstract
A cloned restriction fragment of maize ohloroplast DNA (Bam H1 fragment 5) is shown to contain an open reading frame which encodes a basic protein of 201 amino acid residues with 40-50% sequence homology to E. coli rlbosomal protein St. Based on the experimentally determined sequence homology between the highly conserved bacterial rlbosomal protein L12 and its ohloroplast homologue (Bartsch H., Kimura, H. and Subramanian, A.R. (1982) Proo. Natl. Acad. Sci. USA 79, 6871), we conolude that this reading frame represents the maize chloroplast S4 gene. The nucleotide sequence of a 1100 base pair DNA segment containing the putative gene is presented.