Carotene Synthase Gene and Uses Therefor
Described herein is a novel three domain gene from Schizochytrium, denoted carotene synthase, that encodes a protein with three different enzymatic activities: phytoene dehydrogenase (PD), phytoene synthase (PS), and lycopene cyclase (LC). Also described is the isolated gene encoding the carotene synthase, homologues thereof, the enzyme encoded by such gene, biologically active portions and homologues thereof, recombinant nucleic acid molecules, microorganisms and plants that have been genetically modified to increase or decrease the action of such gene, and methods of producing carotenoids and derivatives thereof or methods of producing microorganisms and lipid products lacking pigmentation using the knowledge of the carotene synthase described herein.
1 . An isolated protein comprising an amino acid sequence selected from the group consisting of:
a. an amino acid sequence selected from the group consisting of SEQ ID NO:3, SEQ ID NO:5, SEQ ID NO:7, SEQ ID NO:9, an amino acid sequence consisting of positions 30 to 1268 of SEQ ID NO:3, and biologically active fragments thereof;
b. an amino acid sequence that is at least about 40% identical to SEQ ID NO:3 or to an amino acid sequence consisting of positions 30 to 1268 of SEQ ID NO:3, wherein said amino acid sequence has the following biological activities: phytoene dehydrogenase (PD) activity, phytoene synthase (PS) activity, and lycopene cyclase (LC) activity;
c. an amino acid sequence that is at least about 40% identical to SEQ ID NO:5, wherein said amino acid sequence has phytoene dehydrogenase (PD) activity;
d. an amino acid sequence that is at least about 40% identical to SEQ ID NO:7, wherein said amino acid sequence has phytoene synthase (PS) activity; and
e. an amino acid sequence that is at least about 40% identical to SEQ ID NO:9, wherein said amino acid sequence has lycopene cyclase (LC) activity.
2 . The isolated protein of claim 1 , wherein said isolated protein comprises an amino acid sequence selected from the group consisting of:
a. an amino acid sequence that is at least about 60% identical to SEQ ID NO:3 or to an amino acid sequence consisting of positions 30 to 1268 of SEQ ID NO:3, wherein said amino acid sequence has the following biological activities:
phytoene dehydrogenase (PD) activity, phytoene synthase (PS) activity, and lycopene cyclase (LC) activity;
b. an amino acid sequence that is at least about 60% identical to SEQ ID NO:5, wherein said amino acid sequence has phytoene dehydrogenase (PD) activity;
c. an amino acid sequence that is at least about 60% identical to SEQ ID NO:7, wherein said amino acid sequence has phytoene synthase (PS) activity; and
d. an amino acid sequence that is at least about 60% identical to SEQ ID NO:9, wherein said amino acid sequence has lycopene cyclase (LC) activity.
3 . The isolated protein of claim 1 , wherein said protein comprises an amino acid sequence selected from the group consisting of:
a. an amino acid sequence that is at least about 80% identical to SEQ ID NO:3 or to an amino acid sequence consisting of positions 30 to 1268 of SEQ ID NO:3, wherein said amino acid sequence has the following biological activities: phytoene dehydrogenase (PD) activity, phytoene synthase (PS) activity, and lycopene cyclase (LC) activity;
b. an amino acid sequence that is at least about 80% identical to SEQ ID NO:5, wherein said amino acid sequence has phytoene dehydrogenase (PD) activity;
c. an amino acid sequence that is at least about 80% identical to SEQ ID NO:7, wherein said amino acid sequence has phytoene synthase (PS) activity; and
d. an amino acid sequence that is at least about 80% identical to SEQ ID NO:9, wherein said amino acid sequence has lycopene cyclase (LC) activity.
4 . The isolated protein of claim 1 , wherein said protein comprises an amino acid sequence selected from the group consisting of:
a. an amino acid sequence that is at least about 95% identical to SEQ ID NO:3 or to an amino acid sequence consisting of positions 30 to 1268 of SEQ ID NO:3, wherein said amino acid sequence has the following biological activities: phytoene dehydrogenase (PD) activity, phytoene synthase (PS) activity, and lycopene cyclase (LC) activity;
b. an amino acid sequence that is at least about 95% identical to SEQ ID NO:5, wherein said amino acid sequence has phytoene dehydrogenase (PD) activity;
c. an amino acid sequence that is at least about 95% identical to SEQ ID NO:7, wherein said amino acid sequence has phytoene synthase (PS) activity; and
d. an amino acid sequence that is at least about 95% identical to SEQ ID NO:9, wherein said amino acid sequence has lycopene cyclase (LC) activity.
5 . The isolated protein of claim 1 , wherein said protein comprises an amino acid sequence selected from the group consisting of: SEQ ID NO:3, SEQ ID NO:5, SEQ ID NO:7, SEQ ID NO:9, an amino acid sequence consisting of positions 30 to 1268 of SEQ ID NO:3, and biologically active fragments thereof.
6 . The isolated protein of claim 1 , wherein said protein comprises an amino acid sequence selected from the group consisting of: SEQ ID NO:3, SEQ ID NO:5, SEQ ID NO:7, SEQ ID NO:9, and an amino acid sequence consisting of positions 30 to 1268 of SEQ ID NO:3.
7 . The isolated protein of claim 1 , wherein said protein comprises any two amino acid sequences selected from the group consisting of SEQ ID NO:5, SEQ ID NO:7 and SEQ ID NO:9.
8 . The isolated protein of claim 1 , wherein said protein comprises SEQ ID NO:5, SEQ ID NO:7 and SEQ ID NO:9.
9 . The isolated protein of claim 1 , wherein said isolated protein is from a Thraustochytriales microorganism.
10 . The isolated protein of claim 1 , wherein said isolated protein is from a Schizochytrium microorganism.
11 . An isolated protein comprising an amino acid sequence selected from the group consisting of:
a. an amino acid sequence comprising SEQ ID NO:5 and SEQ ID NO:7; and
b. an amino acid sequence that is at least about 40% identical to the amino acid sequence of (a), wherein said amino acid sequence has the following biological activities: phytoene dehydrogenase (PD) activity and phytoene synthase (PS) activity.
12 . An isolated antibody that selectively binds to an amino acid sequence selected from the group consisting of: SEQ ID NO:3, SEQ ID NO:5, SEQ ID NO:7, and SEQ ID NO:9.
13 . An isolated nucleic acid molecule comprising a nucleic acid sequence selected from the group consisting of:
a. a nucleic acid sequence encoding an amino acid sequence selected from the group consisting of SEQ ID NO:3, SEQ ID NO:5, SEQ ID NO:7, SEQ ID NO:9, an amino acid sequence consisting of positions 30 to 1268 of SEQ ID NO:3, and biologically active fragments of any of said amino acid sequences;
b. a nucleic acid sequence encoding an amino acid sequence that is at least about 40% identical to SEQ ID NO:3 or to an amino acid sequence consisting of positions 30 to 1268 of SEQ ID NO:3, wherein said amino acid sequence has the following biological activities: phytoene dehydrogenase (PD) activity, phytoene synthase (PS) activity, and lycopene cyclase (LC) activity;
c. a nucleic acid sequence encoding an amino acid sequence that is at least about 40% identical to SEQ ID NO:5, wherein said amino acid sequence has phytoene dehydrogenase (PD) activity;
d. a nucleic acid sequence encoding an amino acid sequence that is at least about 40% identical to SEQ ID NO:7, wherein said amino acid sequence has phytoene synthase (PS) activity;
e. a nucleic acid sequence encoding an amino acid sequence that is at least about 40% identical to SEQ ID NO:9, wherein said amino acid sequence has lycopene cyclase (LC) activity; and
f. a nucleic acid sequence that is fully complementary to any one of the nucleic acid sequences of (a)-(e).
14 . The isolated nucleic acid molecule of claim 13 , wherein said nucleic acid molecule comprises a nucleic acid sequence selected from the group consisting of:
a. a nucleic acid sequence encoding an amino acid sequence that is at least about 60% identical to SEQ ID NO:3 or to an amino acid sequence consisting of positions 30 to 1268 of SEQ ID NO:3, wherein said amino acid sequence has the following biological activities: phytoene dehydrogenase (PD) activity, phytoene synthase (PS) activity, and lycopene cyclase (LC) activity;
b. a nucleic acid sequence encoding an amino acid sequence that is at least about 60% identical to SEQ ID NO:5, wherein said amino acid sequence has phytoene dehydrogenase (PD) activity;
c. a nucleic acid sequence encoding an amino acid sequence that is at least about 60% identical to SEQ ID NO:7, wherein said amino acid sequence has phytoene synthase (PS) activity; and
d. a nucleic acid sequence encoding an amino acid sequence that is at least about 60% identical to SEQ ID NO:9, wherein said amino acid sequence has lycopene cyclase (LC) activity; and
e. a nucleic acid sequence that is fully complementary to any one of the nucleic acid sequences of (a)-(d).
15 . The isolated nucleic acid molecule of claim 13 , wherein said nucleic acid molecule comprises a nucleic acid sequence selected from the group consisting of:
a. a nucleic acid sequence encoding an amino acid sequence that is at least about 80% identical to SEQ ID NO:3 or to an amino acid sequence consisting of positions 30 to 1268 of SEQ ID NO:3, wherein said amino acid sequence has the following biological activities: phytoene dehydrogenase (PD) activity, phytoene synthase (PS) activity, and lycopene cyclase (LC) activity;
b. a nucleic acid sequence encoding an amino acid sequence that is at least about 80% identical to SEQ ID NO:5, wherein said amino acid sequence has phytoene dehydrogenase (PD) activity;
c. a nucleic acid sequence encoding an amino acid sequence that is at least about 80% identical to SEQ ID NO:7, wherein said amino acid sequence has phytoene synthase (PS) activity;
d. a nucleic acid sequence encoding an amino acid sequence that is at least about 80% identical to SEQ ID NO:9, wherein said amino acid sequence has lycopene cyclase (LC) activity; and
e. a nucleic acid sequence that is fully complementary to any one of the nucleic acid sequences of (a)-(d).
16 . The isolated nucleic acid molecule of claim 13 , wherein said nucleic acid molecule comprises a nucleic acid sequence selected from the group consisting of:
a. a nucleic acid sequence encoding an amino acid sequence that is at least about 95% identical to SEQ ID NO:3 or to an amino acid sequence consisting of positions 30 to 1268 of SEQ ID NO:3, wherein said amino acid sequence has the following biological activities: phytoene dehydrogenase (PD) activity, phytoene synthase (PS) activity, and lycopene cyclase (LC) activity;
b. a nucleic acid sequence encoding an amino acid sequence that is at least about 95% identical to SEQ ID NO:5, wherein said amino acid sequence has phytoene dehydrogenase (PD) activity;
c. a nucleic acid sequence encoding an amino acid sequence that is at least about 95% identical to SEQ ID NO:7, wherein said amino acid sequence has phytoene synthase (PS) activity;
d. a nucleic acid sequence encoding an amino acid sequence that is at least about 95% identical to SEQ ID NO:9, wherein said amino acid sequence has lycopene cyclase (LC) activity; and
e. a nucleic acid sequence that is fully complementary to any one of the nucleic acid sequences of (a)-(d).
17 . The isolated nucleic acid molecule of claim 13 , wherein said nucleic acid molecule comprises a nucleic acid sequence encoding an amino acid sequence selected from the group consisting of: SEQ ID NO:3, SEQ ID NO:5, SEQ ID NO:7, SEQ ID NO:9, and an amino acid sequence consisting of positions 30 to 1268 of SEQ ID NO:3.
18 . The isolated nucleic acid molecule of claim 13 , wherein said nucleic acid sequence is selected from the group consisting of: SEQ ID NO:1, SEQ ID NO:2, SEQ ID NO:4, SEQ ID NO:6 and SEQ ID NO:8.
19 . The isolated nucleic acid molecule of claim 13 , wherein said nucleic acid sequence encodes any two amino acid sequences selected from the group consisting of SEQ ID NO:5, SEQ ID NO:7 and SEQ ID NO:9.
20 . The isolated nucleic acid molecule of claim 13 , wherein said nucleic acid sequence encodes SEQ ID NO:5, SEQ ID NO:7 and SEQ ID NO:9.
21 . A recombinant nucleic acid molecule comprising an isolated nucleic acid molecule operatively linked to a transcription control sequence, said isolated nucleic acid molecule comprising a nucleic acid sequence selected from the group consisting of:
a. a nucleic acid sequence encoding an amino acid sequence selected from the group consisting of SEQ ID NO:3, SEQ ID NO:5, SEQ ID NO:7, SEQ ID NO:9, an amino acid sequence consisting of positions 30 to 1268 of SEQ ID NO:3, and biologically active fragments of any of said amino acid sequences;
b. a nucleic acid sequence encoding an amino acid sequence that is at least about 40% identical to SEQ ID NO:3 or to an amino acid sequence consisting of positions 30 to 1268 of SEQ ID NO:3, wherein said amino acid sequence has the following biological activities: phytoene dehydrogenase (PD) activity, phytoene synthase (PS) activity, and lycopene cyclase (LC) activity;
c. a nucleic acid sequence encoding an amino acid sequence that is at least about 40% identical to SEQ ID NO:5, wherein said amino acid sequence has phytoene dehydrogenase (PD) activity;
d. a nucleic acid sequence encoding an amino acid sequence that is at least about 40% identical to SEQ ID NO:7, wherein said amino acid sequence has phytoene synthase (PS) activity; and
e. a nucleic acid sequence encoding an amino acid sequence that is at least about 95% identical to SEQ ID NO:9, wherein said amino acid sequence has lycopene cyclase (LC) activity.
22 . The recombinant nucleic acid molecule of claim 21 , wherein said transcription control sequence is a tissue-specific transcription control sequence.
23 . The recombinant nucleic acid molecule of claim 21 , further comprising a targeting sequence.
24 . A recombinant cell that has been transformed with the recombinant nucleic acid molecule of claim 21 .
25 . A genetically modified microorganism for producing a carotenoid by a biosynthetic process, said microorganism being transformed with a recombinant nucleic acid molecule according to claim 21 .
26 . A genetically modified plant for producing a carotenoid by a biosynthetic process, said plant being transformed with a recombinant nucleic acid molecule according to claim 21 .
27 . A genetically modified microorganism for producing a carotenoid by a biosynthetic process, wherein said microorganism comprises a nucleic acid molecule encoding a carotene synthase and wherein said nucleic acid molecule encoding said carotene synthase has been modified to increase the expression or biological activity of said carotene synthase, said carotene synthase comprising an amino acid sequence selected from the group consisting of:
a. an amino acid sequence selected from the group consisting of SEQ ID NO:3, SEQ ID NO:5, SEQ ID NO:7, SEQ ID NO:9, and an amino acid sequence consisting of positions 30 to 1268 of SEQ ID NO:3;
b. an amino acid sequence that is at least about 40% identical to SEQ ID NO:3 or to an amino acid sequence consisting of positions 30 to 1268 of SEQ ID NO:3, wherein said amino acid sequence has the following biological activities:
phytoene dehydrogenase (PD) activity, phytoene synthase (PS) activity, and lycopene cyclase (LC) activity;
c. an amino acid sequence that is at least about 40% identical to SEQ ID NO:5, wherein said amino acid sequence has phytoene dehydrogenase (PD) activity;
d. an amino acid sequence that is at least about 40% identical to SEQ ID NO:7, wherein said amino acid sequence has phytoene synthase (PS) activity; and
e. an amino acid sequence that is at least about 40% identical to SEQ ID NO:9, wherein said amino acid sequence has lycopene cyclase (LC) activity.
28 . The genetically modified microorganism of claim 27 , wherein said nucleic acid molecule encoding a carotene synthase is an endogenous gene in said microorganism.
29 . The genetically modified microorganism of claim 27 , wherein said microorganism has been transformed with a nucleic acid molecule encoding said carotene synthase.
30 . The genetically modified microorganism of claim 29 , wherein said microorganism is a Thraustochytriales microorganism.
31 . The genetically modified microorganism of claim 29 , wherein said microorganism is a Schizochytrium.
32 . The genetically modified microorganism of claim 27 , wherein said microorganism comprises an endogenous gene encoding said carotene synthase and has been transformed with a recombinant nucleic acid molecule encoding said carotene synthase, wherein one or both of said gene and said recombinant nucleic acid molecule has been modified to increase the expression or biological activity of said carotene synthase.
33 . The genetically modified microorganism of claim 27 , wherein said microorganism is a Thraustochytriales microorganism.
34 . The genetically modified microorganism of claim 27 , wherein said microorganism is a Schizochytrium microorganism.
35 . A biomass comprising genetically modified microorganism comprising a nucleic acid molecule encoding a carotene synthase and wherein said nucleic acid molecule encoding said carotene synthase has been modified to increase the expression or biological activity of said carotene synthase, said carotene synthase comprising an amino acid sequence selected from the group consisting of:
a. an amino acid sequence selected from the group consisting of SEQ ID NO:3, SEQ ID NO:5, SEQ ID NO:7, SEQ ID NO:9, and an amino acid sequence consisting of positions 30 to 1268 of SEQ ID NO:3;
b. an amino acid sequence that is at least about 40% identical to SEQ ID NO:3 or to an amino acid sequence consisting of positions 30 to 1268 of SEQ ID NO:3, wherein said amino acid sequence has the following biological activities: phytoene dehydrogenase (PD) activity, phytoene synthase (PS) activity, and lycopene cyclase (LC) activity;
c. an amino acid sequence that is at least about 40% identical to SEQ ID NO:5, wherein said amino acid sequence has phytoene dehydrogenase (PD) activity;
d. an amino acid sequence that is at least about 40% identical to SEQ ID NO:7, wherein said amino acid sequence has phytoene synthase (PS) activity; and
e. an amino acid sequence that is at least about 40% identical to SEQ ID NO:9, wherein said amino acid sequence has lycopene cyclase (LC) activity.
36 . A food product comprising the biomass of claim 35 .
37 . A pharmaceutical product comprising the biomass of claim 35 .
38 . A method to produce a carotenoid by a biosynthetic process, comprising culturing in a fermentation medium a genetically modified microorganism that has increased expression or biological activity of a carotene synthase, said carotene synthase comprising an amino acid sequence selected from the group consisting of:
a. an amino acid sequence selected from the group consisting of SEQ ID NO:3, SEQ ID NO:5, SEQ ID NO:7, SEQ ID NO:9, an amino acid sequence consisting of positions 30 to 1268 of SEQ ID NO:3, and biologically active fragments thereof;
b. an amino acid sequence that is at least about 40% identical to SEQ ID NO:3 or to an amino acid sequence consisting of positions 30 to 1268 of SEQ ID NO:3, wherein said amino acid sequence has the following biological activities:
phytoene dehydrogenase (PD) activity, phytoene synthase (PS) activity, and lycopene cyclase (LC) activity;
c. an amino acid sequence that is at least about 40% identical to SEQ ID NO:5, wherein said amino acid sequence has phytoene dehydrogenase (PD) activity;
d. an amino acid sequence that is at least about 40% identical to SEQ ID NO:7, wherein said amino acid sequence has phytoene synthase (PS) activity; and
e. an amino acid sequence that is at least about 40% identical to SEQ ID NO:9, wherein said amino acid sequence has lycopene cyclase (LC) activity.
39 . The method of claim 38 , wherein said microorganism has been transformed with a recombinant nucleic acid molecule encoding said carotene synthase.
40 . The method of claim 39 , wherein said microorganism is a Thraustochytriales microorganism.
41 . The method of claim 39 , wherein said microorganism is a Schizochytrium.
42 . The method of claim 38 , wherein said microorganism comprises an endogenous gene encoding said carotene synthase, and wherein said gene has been genetically modified to increase the expression or biological activity of said carotene synthase.
43 . The method of claim 38 , wherein said microorganism comprises an endogenous gene encoding said carotene synthase and has been transformed with a recombinant nucleic acid molecule encoding said carotene synthase, wherein one or both of said gene and said recombinant nucleic acid molecule has been modified to increase the expression or at least one biological activity of said carotene synthase.
44 . The method of claim 38 , wherein said microorganism is a Thraustochytriales microorganism.
45 . The method of claim 38 , wherein said microorganism is a Schizochytrium.
46 . A method to produce a carotenoid by a biosynthetic process, comprising growing a genetically modified plant that has been transformed with a recombinant nucleic acid molecule encoding a protein comprising an amino acid sequence selected from the group consisting of:
a. an amino acid sequence selected from the group consisting of SEQ ID NO:3, SEQ ID NO:5, SEQ ID NO:7, SEQ ID NO:9, an amino acid sequence consisting of positions 30 to 1268 of SEQ ID NO:3, and biologically active fragments thereof;
b. an amino acid sequence that is at least about 40% identical to SEQ ID NO:3 or to an amino acid sequence consisting of positions 30 to 1268 of SEQ ID NO:3, wherein said amino acid sequence has the following biological activities:
phytoene dehydrogenase (PD) activity, phytoene synthase (PS) activity, and lycopene cyclase (LC) activity;
c. an amino acid sequence that is at least about 40% identical to SEQ ID NO:5, wherein said amino acid sequence has phytoene dehydrogenase (PD) activity;
d. an amino acid sequence that is at least about 40% identical to SEQ ID NO:7, wherein said amino acid sequence has phytoene synthase (PS) activity; and
e. an amino acid sequence that is at least about 40% identical to SEQ ID NO:9, wherein said amino acid sequence has lycopene cyclase (LC) activity.
47 . The method of claim 46 , wherein said recombinant nucleic acid molecule encodes a protein having phytoene dehydrogenase (PD) activity and phytoene synthase (PS) activity, but not having lycopene cyclase (LC) activity.
48 . An oligonucleotide, comprising at least 12 contiguous nucleotides of a nucleic acid sequence selected from the group consisting of: SEQ ID NO:1, SEQ ID NO:2, SEQ ID NO:4, SEQ ID NO:6, SEQ ID NO:8, and a nucleic acid sequence fully complementary thereto.
49 . A genetically modified microorganism lacking pigmentation, wherein said microorganism has been genetically modified to selectively delete or inactivate a carotene synthase gene or portion thereof encoding a functional domain, wherein said carotene synthase gene comprises a nucleic acid sequence selected from the group consisting of:
a. a nucleic acid sequence encoding SEQ ID NO:3; and
b. a nucleic acid sequence encoding an amino acid sequence that is at least about 40% identical to SEQ ID NO:3, wherein a protein having said amino acid sequence has a biological activity selected from the group consisting of phytoene dehydrogenase (PD) activity, phytoene synthase (PS) activity, and lycopene cyclase (LC) activity.
50 . The genetically modified microorganism of claim 49 , wherein said carotene synthase gene comprises a nucleic acid sequence represented by SEQ ID NO:3.
51 . The genetically modified microorganism of claim 49 , wherein said microorganism is a Thraustochytriales microorganism.
52 . The genetically modified microorganism of claim 49 , wherein said microorganism is a Schizochytrium.
53 . The genetically modified microorganism of claim 49 , wherein said carotene synthase gene has been modified in a regulatory region to inhibit expression of the gene.
54 . The genetically modified microorganism of claim 49 , wherein said carotene synthase gene has been partially or completely deleted so that the microorganism does not produce a functional carotene synthase.
55 . The genetically modified microorganism of claim 49 , wherein said carotene synthase gene has been mutated or inactivated by targeted homologous recombination with a nucleic acid sequence that hybridizes to said carotene synthase gene and includes a heterologous nucleic acid sequence that disrupts the coding region of said carotene synthase gene.
56 . A biomass comprising genetically modified microorganisms that have reduced pigmentation as compared to a wild-type microorganism of the same species, wherein said microorganisms have been genetically modified to selectively delete or inactivate a carotene synthase gene, wherein said carotene synthase gene comprises a nucleic acid sequence selected from the group consisting of:
a. a nucleic acid sequence encoding SEQ ID NO:3; and
b. a nucleic acid sequence encoding an amino acid sequence that is at least about 40% identical to SEQ ID NO:3, wherein a protein having said amino acid sequence has a biological activity selected from the group consisting of phytoene dehydrogenase (PD) activity, phytoene synthase (PS) activity, and lycopene cyclase (LC) activity.
57 . The biomass of claim 56 , wherein said carotene synthase gene comprises a nucleic acid sequence encoding SEQ ID NO:3.
58 . The biomass of claim 56 , wherein said microorganisms are from the order Thraustochytriales.
59 . A food product comprising the biomass according to claim 56 .
60 . A method for producing lipids lacking pigmentation from a biosynthetic process, comprising culturing under conditions effective to produce said lipids genetically modified microorganisms, wherein said microorganisms have been genetically modified to selectively delete or inactivate a carotene synthase gene, wherein said carotene synthase gene comprises a nucleic acid sequence selected from the group consisting of:
a. a nucleic acid sequence encoding SEQ ID NO:3; and
b. a nucleic acid sequence encoding an amino acid sequence that is at least about 40% identical to SEQ ID NO:3, wherein a protein having said amino acid sequence has a biological activity selected from the group consisting of phytoene dehydrogenase (PD) activity, phytoene synthase (PS) activity, and lycopene cyclase (LC) activity.
61 . The method of claim 60 , wherein said microorganisms are from the order Thraustochytriales.
62 . A method for recovering lipids lacking pigmentation from a biosynthetic process, comprising recovering lipids from a culture of genetically modified microorganisms, wherein said microorganisms have been genetically modified to selectively delete or inactivate a carotene synthase gene, wherein said carotene synthase gene comprises a nucleic acid sequence selected from the group consisting of:
a. a nucleic acid sequence encoding SEQ ID NO:3; and
b. a nucleic acid sequence encoding an amino acid sequence that is at least about 40% identical to SEQ ID NO:3, wherein a protein having said amino acid sequence has a biological activity selected from the group consisting of phytoene 10 dehydrogenase (PD) activity, phytoene synthase (PS) activity, and lycopene cyclase (LC) activity.
63 . The method of claim 62 , wherein said microorganisms are from the order Thraustochytriales.
64 . Lipids lacking pigmentation that are recovered from a culture of genetically modified microorganisms, wherein said microorganisms have been genetically modified to selectively delete or inactivate a carotene synthase gene, wherein said carotene synthase gene comprises a nucleic acid sequence selected from the group consisting of:
a. a nucleic acid sequence encoding SEQ ID NO:3; and
b. a nucleic acid sequence encoding an amino acid sequence that is at least about 40% identical to SEQ ID NO:3, wherein a protein having said amino acid sequence has a biological activity selected from the group consisting of phytoene dehydrogenase (PD) activity, phytoene synthase (PS) activity, and lycopene cyclase (LC) activity.
65 . The lipids of claim 64 , wherein said microorganisms are from the order Thraustochytriales.
66 . A product comprising the lipids according to claim 64 .
67 . The product of claim 66 , which is a food product.
68 . The product of claim 66 , which is a pharmaceutical product.
69 . A method for producing a carotenoid comprising contacting a substrate with an isolated carotene synthase under conditions sufficient to produce a carotenoid;
wherein said isolated carotene synthase comprises an amino acid sequence selected from the group consisting of:
a. an amino acid sequence selected from the group consisting of SEQ ID NO:3, SEQ ID NO:5, SEQ ID NO:7, SEQ ID NO:9, an amino acid sequence consisting of positions 30 to 1268 of SEQ ID NO:3, and biologically active fragments thereof;
b. an amino acid sequence that is at least about 40% identical to SEQ ID NO:3 or to an amino acid sequence consisting of positions 30 to 1268 of SEQ ID NO:3, wherein said amino acid sequence has the following biological activities:
phytoene dehydrogenase (PD) activity, phytoene synthase (PS) activity, and lycopene cyclase (LC) activity;
c. an amino acid sequence that is at least about 40% identical to SEQ ID NO:5, wherein said amino acid sequence has phytoene dehydrogenase (PD) activity;
d. an amino acid sequence that is at least about 40% identical to SEQ ID NO:7, wherein said amino acid sequence has phytoene synthase (PS) activity; and
e. an amino acid sequence that is at least about 40% identical to SEQ ID NO:9, wherein said amino acid sequence has lycopene cyclase (LC) activity.