The nucleotide sequence of a 12.5 kb fragment localized to the right arm of chromosome II of Saccharomyces cerevisiae has been determined. The sequence contains eight putative genes. Two of them are contiguous and represent two ribosomal protein genes: SUP46 and URP1. SUP46 is implicated in translation fidelity and encodes the ribosomal protein S13. URP1 is homologous to the rat ribosomal protein gene L21. The open reading frame (ORF) YBR1245 is similar in its N-terminal part to transcription factors like SRF and MCM1. The ORF YBR1308 shows homology with proteins of the AAA-family (ATPases Associated with diverse cellular Activities). Two genes are predicted to encode putative membrane proteins.