crispr-cas9 gene editing complex from streptococcus pyogenes. the cas9 nuclease protein uses a guide rna sequence to cut dna at a

acid amino associated atoms bacteria biotech cas cas9 cell clustered crispr cure disease dna drug editing embryonic engineering gene genome health interference interspaced model molecular molecule nuclease palindromic pdb4oo8 peptide polymer polypeptide protein pyogenes regularly repeats resistance rna science scientific sgrna short streptococcus structure therapy transactivating virus