Glyceroglycolipid lipase

Abstract

Disclosed is a glyceroglycolipid lipase which is highly safe, can hydrolyze a neutral fat, a glycerophospholipid or a glyceroglycolipid at about pH 6, is thermally stable to some extent, can hydrolyze lecithin, cannot hydrolyze lysolecithin, can rise a bread when used singly in the production of the bread, and has no unpleasant odor. Specifically disclosed is a glyceroglycolipid lipase derived from a filamentous bacterium Aspergillus japonicus.

1 . A glyceroglycolipid lipase having the following properties:
 1) having a molecular weight of approximately 29,000 as determined by SDS-PAGE;   2) hydrolyzing neutral fat, lecithin, and glyceroglycolipid at pH 6.0;   3) having a glyceroglycolipid degradation activity at least 10-fold higher than a lecithin degradation activity at pH ranging from 3.6 to 8.9.   
     
     
         2 . The glyceroglycolipid lipase according to  claim 1 , which further has the following properties:
 4) having a relative degradation activity of at least 80% or more for glyceroglycolipid at pH ranging from 4.1 to 7.7;   5) having a relative degradation activity of at least 80% or more for lecithin at pH ranging from 5.1 to 7.1;   6) not having the hydrolytic activity of 5) at a temperature of 80° C. or higher;   7) having a relative residual degradation activity of 75% or more for glyceroglycolipid at pH ranging from 4.1 to 10.7.   
     
     
         3 . The glyceroglycolipid lipase according to  claim 1  or  2 , which is derived from a filamentous fungus  Aspergillus japonicus.    
     
     
         4 . The glyceroglycolipid lipase according to  claim 3 , wherein the filamentous fungus is  Aspergillus japonicus  strain SANK 11298. 
     
     
         5 . A glyceroglycolipid lipase which is a protein of any one of the following a) to e):
 a) a protein consisting of the amino acid sequence of SEQ ID NO: 2 of the sequence listing;   b) a protein consisting of an amino acid sequence encoded by the nucleotide sequence from nucleotide number 110 to nucleotide number 991 of SEQ ID NO: 1 of the sequence listing;   c) a protein consisting of an amino acid sequence in which one or several amino acids are substituted, deleted, inserted, or added in the amino acid sequence as recited in a) or b), and having a glyceroglycolipid degradation activity;   d) a protein consisting of an amino acid sequence having an amino acid sequence homology of 70% or more with the protein of a), and having a glyceroglycolipid degradation activity;   e) a protein comprising the amino acid sequence as recited in a) or b).   
     
     
         6 . (canceled) 
     
     
         7 . A glyceroglycolipid lipase encoded by a DNA
 a) consisting of the nucleotide sequence from nucleotide number 110 to nucleotide number 991 of SEQ ID NO: 1 of the sequence listing;   b) consisting of a nucleotide sequence having a nucleotide sequence homology of 70% or more with the DNA of a), and encoding a protein having a glyceroglycolipid degradation activity;   c) hybridizing to the DNA of a) under stringent conditions, and encoding a protein having a glyceroglycolipid degradation activity;   d) encoding a protein consisting of the amino acid sequence of SEQ ID NO: 2 of the sequence listing; or   e) comprising the nucleotide sequence from nucleotide number 110 to nucleotide number 991 of SEQ ID NO: 1 of the sequence listing.   
     
     
         8 . An isolated filamentous fungus  Aspergillus japonicus  strain SANK 11298, which has the ability to produce the glyceroglycolipid lipase according to any one of  claims 1  to  5  and  7 . 
     
     
         9 . A method for producing a glyceroglycolipid lipase, comprising 1) and 2):
 1) a step of culturing  Aspergillus japonicus  under conditions under which a glyceroglycolipid lipase is produced, and   2) a step of separating and purifying the glyceroglycolipid lipase from the culture product of 1).   
     
     
         10 . The method according to  claim 9 , wherein said  Aspergillus japonicus  is  Aspergillus japonicus  strain SANK 11298. 
     
     
         11 . A glyceroglycolipid lipase which is produced by the method according to  claim 9  or  10 . 
     
     
         12 . A method for baking, wherein the glyceroglycolipid lipase according to any one of  claims 1  to  5 ,  7  and  11  is used. 
     
     
         13 . The glyceroglycolipid lipase according to any one of  claims 1  to  5 ,  7  and  11 , which is for baking. 
     
     
         14 . A method for baking, comprising baking a raw material in the presence of the glyceroglycolipid lipase of  claim 1 .