Hyperthermostable endoglucanase belonging to gh family 12

A polynucleotide comprising a region that encodes an endoglucanase catalytic domain which comprises:

• (a) a nucleotide sequence that encodes a polypeptide comprising an amino acid sequence represented by SEQ ID NO:
• 3 or SEQ ID NO:
• 11;
• (b) a nucleotide sequence that encodes a polypeptide comprising an amino acid sequence in which at least one amino acid is deleted, substituted, or added in the amino acid sequence represented by SEQ ID NO:
• 3 or SEQ ID NO:
• 1, and having hydrolytic activity using carboxymethyl cellulose as a substrate at least under conditions of a temperature of 110° C. and a pH of 4.0;
• (c) a nucleotide sequence that encodes a polypeptide comprising an amino acid sequence having at least 70% sequence identity with the amino acid sequence represented by SEQ ID NO:
• 3 or SEQ ID NO:
• 11, and having hydrolytic activity using carboxymethyl cellulose as a substrate at least under conditions of a temperature of 110° C. and a pH of 4.0;
• (d) a nucleotide sequence having at least 70% sequence identity with a nucleotide sequence represented by SEQ ID NO:
• 4 or SEQ ID NO:
• 12, and encoding a polypeptide having hydrolytic activity using carboxymethyl cellulose as a substrate at least under conditions of a temperature of 110° C. and a pH of 4.0;
• or
• (e) a nucleotide sequence of a polynucleotide which hybridizes with a polynucleotide comprising a nucleotide sequence represented by SEQ ID NO:
• 4 or SEQ ID NO:
• 12 under a stringent condition, and being a nucleotide sequence that encodes a polypeptide having hydrolytic activity using carboxymethyl cellulose as a substrate at least under conditions of a temperature of 110° C. and a pH of 4.0.