Compilation and analysis of intein sequences
Francine B. Perler , Gary J. Olsen 1 and Eric Adam
Nucleic Acids Research ,
25(6):1087-1094 (1997)
Abstract
We have compiled a list of all the inteins (protein splicing elements) whose
sequences have been published or were available from on-line sequence
databases as of September 18, 1996. Analysis of the 36 available intein
sequences refines the previously described intein motifs and reveals the
presence of another intein motif, Block H. Furthermore, analysis of the new
inteins reshapes our view of the conserved splice junction residues, since
three inteins lack the intein penultimate His seen in prior examples.
Comparison of intein sequences suggests that, in general, (i) inteins present
in the same location within extein homologs from different organisms are
very closely related to each other in paired sequence comparison or
phylogenetic analysis and we suggest that they should be considered intein
alleles; (ii) multiple inteins present in the same gene are no more similar to
each other than to inteins present in different genes; (iii) phylogenetic
analysis indicates that inteins are so divergent that trees with statistically
significant branches cannot be generated except for intein alleles.
