Open AccessExpression and processing of an unusual tRNA gene cluster in the cyanobacterium A nabaena sp. PCC 7120
Author(s) -
PuertoGalán Leonor,
Vioque Agustín
Publication year - 2012
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.2012.02664.x
Subject(s) - transfer rna , rnase p , biology , pseudogene , gene , gene cluster , anabaena , genetics , rna , biochemistry , cyanobacteria , genome , bacteria
A nabaena sp. PCC 7120 is a filamentous cyanobacterium that bears a cluster of 26 t RNA genes and pseudogenes in the delta plasmid. The sequences of these t RNA s suggest that they have been acquired by horizontal gene transfer from another organism. The cluster is transcribed as a single transcript that is quickly processed to individual t RNA s. RN ase P and RN ase Z , in vitro , are able to process precursors containing some of these t RNA s. Deletion of the cluster causes no obvious phenotype or effect on growth under diverse culture conditions, indicating that the t RNA s encoded in the cluster are not required for growth under laboratory conditions, although they are aminoacylated in vivo . We have studied a possible t RNA Ser [t RNA Ser GCU (2)] present in the cluster with a sequence that deviates from consensus. This t RNA is processed in vitro by RN ase P at the expected position. In addition, this t RNA Ser GCU is specifically aminoacylated with serine by an A nabaena sp. PCC 7120 crude extract. These data indicate that t RNA Ser GCU (2) is fully functional, despite its unusual structure. Similar clusters are found in other three cyanobacteria whose genomes have been sequenced.