Phospholipases, nucleic acids encoding them and methods for making and using them

Abstract

The invention provides novel polypeptides having phospholipase activity, including, e.g., phospholipase A, B, C and D activity, patatin activity, phosphatidic acid phosphatases (PAP)) and / or lipid acyl hydrolase (LAH) activity, nucleic acids encoding them and antibodies that bind to them. Industrial methods, e.g., oil degumming, and products comprising use of these phospholipases are also provided.

Description

CROSS REFERENCE TO RELATED APPLICATIONS[0001]This application is a divisional of U.S. patent application Ser. No. (“USSN”) 11 / 625,765, filed Jan. 22, 2007, currently pending; which is a divisional of U.S. Ser. No. 10 / 592,450, filed Jul. 29, 2008, currently pending; which is a National Stage Filing under 35 U.S.C. §371 of international patent application number PCT / US2005 / 07908, filed Mar. 8, 2005; which claims priority to U.S. Ser. No. 10 / 796,907, filed Mar. 8, 2004, now U.S. Pat. No. 7,226,771; which is a continuation-in-part of U.S. Ser. No. 10 / 421,654, filed Apr. 21, 2003, now abandon; which is a non-provisional filing of U.S. Ser. No. 60 / 374,313, filed Apr. 19, 2002, now expired, all of which are incorporated by reference into the specification of this application in there entirety and for all purposes.REFERENCE TO SEQUENCE LISTING[0002]This application includes a sequence listing that is identical to a sequence filed Jan. 22, 2007, in computer readable form with application Ser...

AI Technical Summary

Benefits of technology

[0095]In one aspect of the oil degumming process, the base causes the isomerization of 1,2-DAG, produced by PLC, into 1,3-DAG which provides a nutritional health benefit over 1,2-DAG, e.g., the 1,3-DAG is burned as energy instead of being stored as fat (as is 1,2-DAG). Thus, the invention provides a caustic oil refining process wherein a phospholipase, e.g., an enzyme of the invention, including a PLC, is added “at the front end”, i.e., before adding any acid and caustic, e.g., as illustrated in the exemplary process of FIG. 13. One of the consequences of adding the PLC at the front end of a caustic refining process of the invention (see further discussion, below), and adding the acid and caustic subsequently, is the generation of an elevated level of 1,3-DAG (not 1,2-DAG). This may be a consequence of acid or base-catalyzed acyl migration. Nutritionally, 1,3-DAG is better than 1,2-DAG. Thus, the invention comprises an oil degumming process using a PLC of the invention, whereby the final degummed oil product contains not less than about 0.5%, 1.0%, 2.0%, 3.0%, 4.0% or 5.0% 1,3-DAG.

[0098]In one aspect the oil degumming method further comprises physical removal of gum produced by the degumming process by addition of a hardening substance, e.g., a talc or equivalent. In one aspect, this increases oil gain.

[0105]Also provided is a caustic refining process for hydrolyzing phospholipids in oil (e.g., plant oil) using a polypeptide of the invention to generate diacylglycerol (DAG) and water-soluble phosphate ester. In one aspect, the enzyme of the invention must operate in a caustic refining process, including, optionally low water and / or in a temperature range of about 55° C. to about 70° C. Use of a caustic refining process with low water in this temperature range will maximize yield by increasing DAG and reducing entrained oil. In one aspect, the enzyme used in this caustic refining process of the invention has both very good activity on phosphatidylcholine (PC) and phosphatidylethanolamine (PE), is active between a pH of about pH 6 to pH 9, is active up to 75° C., and is active in low water in oil, e.g., about 2% to 5% water, e.g., the enzyme encoded by the sequence of SEQ ID NO:2, encoded e.g., by SEQ ID NO:1.

[0109]The hydrolysis conditions can comprise a pH of between about pH 3 and pH 10, between about pH 4 and pH 9, or between about pH 5 and pH 8. The hydrolysis conditions can comprise addition of emulsifiers and / or mixing after the contacting of step (c). The methods can comprise addition of an emulsion-breaker and / or heat or cooling (e.g. to between about 4° C. to about −20° C., or less) to promote separation of an aqueous phase. The methods can comprise degumming before the contacting step to collect lecithin by centrifugation and then adding a PLC, a PLC and / or a PLA to remove non-hydratable phospholipids. The methods can comprise water degumming of crude oil to less than 10 ppm phosphorus for edible oils and subsequent physical refining to less than about 50 ppm phosphorus for biodiesel oils. The methods can comprise addition of acid to promote hydration of non-hydratable phospholipids. In one aspect, addition of acid promotes lowering of the calcium and magnesium metal content.

Problems solved by technology

The neutralization process is highly effective in removing free fatty acids and phospholipids but this process also results in significant yield losses and sacrifices in quality.

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