Random sequence analysis of a Geobacillus sp. isolated in Argentina

AMADIO A; ZANDOMENI RO

Bariloche, Argentina

Congreso; XXXIX Reunión Anual SAIB; 2003

A thermophilic bacillus isolated from a thermal spring in Argentina was classified as a Geobacillus sp. by sequencing of 16S ribosomal encoding gene (16S rDNA). A genomic library was constructed using Sau3A digested DNA with fragment size ranging from 2.5-3 kb in pGEM3Z plasmid vector. Two hundred and eighty-five random clones were selected and plasmid DNA was purified. Sequences from both sides of the inserts were obtained (570 sequences) giving approximately a total of 256,000 bp sequenced. A low number of sequences gave significant identities (<10% of clones) using BLASTN to search NCBI databases. Using BLASTX most sequences (>90% of clones) gave similarities with different proteins including several with biotechnological relevance like alpha-amylase, glycogen synthase, DNA topoisomerase, catalase, DNA methylases, phosporylases, and peptidases. Other group of genes involved in metabolic pathways and transport suggest the existence in this microorganism of such processes. The discovery and availability of al least 30 plasmids with the complete gene sequence will facilitate their subcloning and expression in heterologous systems.