(EN) A PREPARATION EXHIBITING ENZYMATIC ACTIVITY AND HAVING THE CAPABILITY OF DELIGNIFYING WOOD PULP AT A TEMPERATURE OF AT LEAST 65°C AND A PH OF AT LEAST 9, IS DESCRIBED. SAID PREPARATION IS OBTAINABLE BY AEROBIC FERMENTATION OF A BACILLUS STEAROTHERMOPHILUS STRAIN SELECTED FROM THE DEPOSITED STRAINS NCIMB 40221 AND NCIMB 40222 AND MUTANTS AND VARIANTS THEREOF.@ALSO, THE DEPOSITED STRAINS NCIMB 40221 AND NCIMB 40222 AND MUTANTS AND VARIANTS THEREOF ARE COMPRISED BY THE INVENTION.@FURTHER, A METHOD OF PRODUCING SAID PREPARATION AND A PROCESS COMPRISING TREATMENT OF WOOD PULP WITH SAID PREPARATION, ARE DISCLOSED.@MOREOVER, THE INVENTION COMPRISES APPLICATIONS OF SAID PREPARATION AS WOOD PULP AND FLUFF PULP TREATED WITH SAID PREPARATION, AND PAPER, BOARD AND FLUFF MADE FROM A WOOD PULP TREATED WITH SAID PREPARATION.@ADDITIONALLY, DNA AND RNA PROBES WHICH RECOGNIZE THE NUCLEOTIDE SEQUENCE CODING FOR A SPECIFIED AMINO ACID SEQUENCE, AND ALSO AN ANTIBODY WHICH BINDS TO SAID AMINO ACID SEQUENCE ARE INCLUDED.