def bestscanseq(self,seq):
        """
        m.bestscanseq(seq) -- Return score,sequence of the best match to the motif in the supplied sequence
        """
        matches,endpoints,scores = self.scan(seq,-100)
        t = zip(scores,matches)
        t.sort()
        bestseq   = t[-1][1]
        bestscore = t[-1][0]
        return bestscore, bestseq