Hydrophobic cluster analysis and classification of sixteen bacterial alginate lyases

Sixteen alginate lyases whose primary sequences have been reported were com pared, and classified into the following three groups on the basis of the i dentity of their primary sequences. Strong homology (> 50%): A-AlgL, A-AlgL *, P-AlgL, P-AlgL*, and AlgA; weak homology (> 20%): ALY, AlxM, P-Aly, K-Al y, AlyPG, AlgVGI, AlgVGII, and AlgVGIII; little homology (< 20%): ALYII, Al -III, and AlgVMI. Using hydrophobic cluster analysis (HCA), a secondary str ucture prediction method, the sixteen alginate lyases were placed into the following classes. Class 1: AlgA, A-AlgL, A-AlgL*, P-AlgL, and P-AlgL*; Cla ss 2: AlgVMI and Al-III; Class 3: ALY and AlxM; Class 4A: ALYII, K-Aly, P-A ly, and AlyPG; Class 4B: AlgVGI and AlgVGII; Class 5: AlgVGIII, which is pu t in a class of its own, because it is unlike any of the other alginate lya ses.