Sometimes synonymous mutations, which do not lead to a change in the protein sequence but which may still have major negative effects on the ability of bacteria to survive, occur in DNA.
New research in the journal Molecular Biology and Evolution shows that an organism can efficiently compensate for the negative effects.
For a long time it has been believed that synonymous mutations are 'silent', i.e. that they have no effect - positive or negative - on the gene product (protein) or on the growth and survival of the organism. However, in recent years several studies have shown that these mutations still often cause problems for the organism even though they do not change the protein sequence.