Needleman-Wunsch Algorithm
General algorithm for sequence comparison
Maximise a similarity score, to give ‘maximum match’
Maximum match = largest number of residues of one sequence that can be matched with another allowing for all possible deletions
Finds the best GLOBAL alignment of any two sequences
N-W involves an iterative matrix method of calculation
- All possible pairs of residues (bases or amino acids) - one from each sequence - are represented in a 2-dimensional array
- All possible alignments (comparisons) are represented by pathways through this array