Abstract: A method for producing a protein by culturing a cell capable of expressing the protein and which contains a methylotrophic yeast promoter for an enzyme of the methanol metabolic pathway controlling expression of the protein, in a fermentative batch process comprising a batch phase and a feeding phase, under conditions such that dissolved oxygen is continually present in the culture medium throughout the process, and about 1% to about 100% of the carbon source during the feeding phase is a sugar or sugar polymer, which sugar or sugar polymer is provided in such an amount that the sugar or sugar polymer is continually depleted by the cell and therefore is substantially undetectable in the culture medium; and isolating the protein on completion of the feeding phase.

Abstract: Novel proteins of Flavobacrerium sp. R1534 and the DNA sequences which encode these proteins are disclosed which provide an improved biosynthetic pathway from farnesyl pyrophosphate and isopentyl pyrophosphate to various carotenoid precursors and carotenoids, especially .beta.-carotene, lycopene, zeaxanthin and cantaxanthin. Processes are also provided for preparing zeaxanthin by culturing a transformed host cell containing an expression cassette that includes a polynucleotide having a DNA sequence which encodes the GGPP synthase of Flavobacterium sp. R1534 (crtE), the prephytoene synthase of Flavobacterium sp. R1534 (crtB), the phytoene desaturase of Flavobacterium sp. R1534 (crtI), the lycopene cyclase of Flavobacterium sp. R1534 (crtY), or the .beta.-carotene hydroxylase of Flavobacterium sp. R1534 (crtZ). The polynucleotide is substantially free of other polynucleotides of Flavobacterium sp. R1534. The process further includes isolating the zeaxanthin from such cells or the culture medium.

Abstract: Novel proteins of Flavobacterium sp. R1534 and the DNA sequences which encode these proteins are disclosed which provide an improved biosynthetic pathway from farnesyl pyrophosphate and isopentyl pyrophosphate to various carotenoid precursors and carotenoids, especially .beta.-carotene, lycopene, zeaxanthin and cantaxanthin.