Nucleotide sequence of a gene cluster encoding ribosomal proteins in the thermoacidophilic crenarchaeon Sulfolobus acidocaldarius

A 1.6 kb genomic DNA fragment derived from the extremely thermoacidophilic archaeon Sulfolobus acidocaldarius (DSM 639) comprises four open reading frames. The sequence contains three genes encoding crenarchaeal ribosomal proteins with apparent molecular masses of 6.3 kDa, 15.2 kDa and 9.9 kDa, which all represent strongly basic properties. These were identified by sequence comparison as RL46, RL31 and RL33. One open reading frame encodes a new polypeptide (22.1 kDa, pI = 7.3) with no homology to known proteins. The latter is transcribed as a common mRNA with RL46 and RL31. This gene cluster immediately precedes another cluster including genes encoding the putative SRP receptor alpha subunit as well as the putative secEp.