A DNA represented by SEQ ID NO:1, and an amino acid sequence coded for therewith. The DNA and the sequence are those of the submit a &cir& _ of a (1}3)- beta -D-glucan-sensitive factor originating in Limulus amoebocytes and have a high affinity for (1}3)- beta -D-glucan in the cell wall of a fungus. Therefore they are useful for clinically diagnosing mycosis, as an antibacterial agent to be used in combination with an anti-fungal agent, and for removing fungi.
