METHOD OF PRODUCING 2'-FUCOSYLLACTOSE USING FUCOSYLTRANSFERASE DERIVED FROM PSEUDOPEDOBACTER SALTANS

Abstract

Disclosed is a method for producing 2′-fucosyllactose from a recombinant Corynebacterium sp. introduced with fucosyltransferase derived from Pseudopedobacter saltans. The recombinant Corynebacterium sp. microorganism introduced with fucosyltransferase derived from Pseudopedobacter saltans is capable of producing 2′-fucosyllactose at a high concentration, high yield and high productivity.

Claims

1. A recombinant Corynebacterium sp. microorganism, which is transformed to express α-1,2-fucosyltransferase having an amino acid sequence set forth in SEQ ID NO: 5 derived from Pseudopedobacter saltans, is transformed to express GDP-D-mannose-4,6-dehydratase, is transformed to express GDP-L-fucose synthase, and is transformed to express lactose permease, wherein the recombinant Corynebacterium sp. microorganism has phosphomannomutase and GTP-mannose-1-phosphate guanylyltransferase.

2. The recombinant Corynebacterium sp. microorganism according to claim 1, wherein the recombinant Corynebacterium sp. microorganism comprises any one selected from Corynebacterium glutamicum, Corynebacterium ammoniagenes and Corynebacterium thermoaminogenes.

3. The recombinant Corynebacterium sp. microorganism according to claim 1, wherein the α-1,2-fucosyltransferase having an amino acid sequence set forth in SEQ ID NO: 5 is encoded by a nucleic acid sequence set forth in SEQ ID NO: 4.

4. The recombinant Corynebacterium sp. microorganism according to claim 1, wherein the recombinant Corynebacterium sp. microorganism is transformed to overexpress phosphomannomutase and is transformed to overexpress GTP-mannose-1-phosphate guanylyltransferase.

5. A method of producing 2′-fucosyllactose comprising culturing, in a medium supplemented with lactose, the recombinant Corynebacterium sp. microorganism according to claim 1.

6. The method according to claim 5, wherein the medium further comprises glucose.

Description

DESCRIPTION OF DRAWINGS

[0017] The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

[0018] FIG. 1 is a schematic diagram showing pFGW(Ps) plasmids;

[0019] FIG. 2 a schematic diagram showing pXIL plasmids;

[0020] FIG. 3 a schematic diagram showing pFGW(Hp) plasmids;

[0021] FIG. 4 shows the result of culture of a recombinant strain introduced with fucosyltransferase derived from Helicobacter pylori (.circle-solid.: Dried cell weight, .square-solid.: Lactose, .Math.: Glucose, .diamond-solid.: 2′-FL, ⋄: Lactate, and ∘: Acetate); and

[0022] FIG. 5 shows the result of culture of a recombinant strain introduced with fucosyltransferase derived from Pseudopedobacter saltans (.circle-solid.: Dried cell weight, .square-solid.: Lactose, .Math.: Glucose, .diamond-solid.: 2′-FL, ⋄: Lactate, and ∘: Acetate).

BEST MODE

[0023] In one aspect, the present invention is directed to a recombinant Corynebacterium sp. microorganism, which is transformed to express α-1,2-fucosyltransferase having the amino acid sequence set forth in SEQ ID NO: 5 derived from Pseudopedobacter saltans, is transformed to express GDP-D-mannose-4,6-dehydratase, is transformed to express GDP-L-fucose synthase, and is transformed to express lactose permease, wherein the recombinant Corynebacterium sp. microorganism has phosphomannomutase and GTP-mannose-1-phosphate guanylyltransferase.

[0024] The recombinant Corynebacterium sp. microorganism preferably includes any one selected from Corynebacterium glutamicum, Corynebacterium ammoniagenes and Corynebacterium thermoaminogenes.

[0025] Meanwhile, since Brevibacterium flavum is currently classified as Corynebacterium glutamicum, Brevibacterium flavum strains also fall within the scope of the present invention.

[0026] In addition, since, according to the UniProt database, Brevibacterium saccharolyticum is used as a synonym for Corynebacterium glutamicum, and Brevibacterium lactofermentum is another name for Corynebacterium glutamicum, Brevibacterium saccharolyticum and Brevibacterium lactofermentum also fall within the scope of the present invention (W. LIEBL et al. INTERNATIONAL JOURNAL OF SYSTEMATIC BACTERIOLOGY, Apr. 1991, p. 255-260; LOTHAR EGGELING et al. JOURNAL OF BIOSCIENCE AND BIOENGINEERING Vol. 92, No. 3,201-213. 2001; Jill A. Haynes et al. FEMS Microbiology Letters 61 (1989) 329-334).

[0027] The prevent inventors obtained Korean Patent No. 10-17312630000 (Apr. 24, 2017), entitled “Method for producing 2′-fucosyllactose using Corynebacterium”. Accordingly, in accordance with the present invention, by inserting a fucosyltransferase derived from

[0028] Pseudopedobacter saltans into Corynebacterium, 2′-fucosyllactose is able to be produced in significantly higher amounts compared to 2′-fucosyllactose produced by inserting a conventional fucosyltransferase derived from Helicobacter pylori into Corynebacterium.

[0029] Meanwhile, unlike conventionally used Escherichia coli, Corynebacterium glutamicum or Corynebacterium ammoniagenes is considered to be a GRAS (generally recognized as safe) strain which does not produce endotoxins and is widely used for industrially producing amino acids and nucleic acids as food additives. Accordingly, Corynebacterium glutamicum or Corynebacterium ammoniagenes is considered to be a strain suitable for the production of food and medicinal materials while advantageously eliminating customer fears about safety.

[0030] However, since Escherichia coli, and Corynebacterium sp. microorganisms including Corynebacterium glutamicum, Corynebacterium ammoniagenes and Corynebacterium thermoaminogenes have inherently different genetic properties, strategies different from those for Escherichia coli should be applied to Corynebacterium. Escherichia coli and Corynebacterium glutamicum are the same in that external α-1,2-fucosyltransferase should be basically introduced in order to produce 2′-fucosyllactose. However, GDP-D-mannose-4,6-degydratase (Gmd), GDP-L-fucose synthase (WcaG), and lactose permease (LacY) should be further introduced into the Corynebacterium sp. microorganism.

[0031] At this time, in the recombinant Corynebacterium sp. microorganism of the present invention, α-1,2-fucosyltransferase having the amino acid sequence set forth in SEQ ID NO: 5 is preferably encoded by the nucleic acid sequence set forth in SEQ ID NO: 4, and genes encoding GDP-D-mannose-4,6-dehydratase (Gmd), GDP-L-fucose synthase, GDP-4-keto-6-deoxymannose-3,5-epimerase-4-reductase (WcaG) and lactose permease (LacY) may be conventionally known genes, and preferably, genes derived from E. coli are used. However, it should be noted that lactose permease (LacY) is an enzyme involved in transporting lactose present outside the strain to the inside thereof. However, since incorporating a Lac operon in the present invention aims at introducing lactose, there is no need to incorporate lacA genes, and it is sufficient simply for lacY genes to be incorporated.

[0032] Meanwhile, since the recombinant Corynebacterium sp. microorganism has genes encoding phosphomannomutase (ManB) and GTP-mannose-1-phosphate guanylyltransferase (ManC) and thus are capable of expressing these enzymes. For this reason, it is not necessary to overexpress these enzymes. However, it is necessary to overexpress such enzymes for mass-production. Therefore, the recombinant Corynebacterium sp. microorganism is preferably transformed to overexpress phosphomannomutase and is transformed to overexpress GTP-mannose-1-phosphate guanylyltransferase.

[0033] In another aspect, the present invention is directed to a method of producing 2′-fucosyllactose including culturing, in a medium supplemented with lactose, the recombinant Corynebacterium sp. microorganism according to the present invention. In accordance with the following experiment of the present invention, the recombinant Corynebacterium sp. microorganism was capable of producing 2′-fucosyllactose at a high concentration, high yield and high productivity compared to a conventional strain.

[0034] Meanwhile, regarding the method for producing 2′-fucosyllactose according to the present invention, the medium preferably further includes glucose. By adding glucose to the medium, the growth of a strain can be facilitated, and 2′-fucosyllactose can thus be produced at higher productivity.

[0035] Meanwhile, the method for producing 2′-fucosyllactose according to the present invention is preferably carried out through fed-batch culture that involves further supplying glucose or lactose. The reason for this is that continuous supply of glucose or lactose through fed-batch culture can further facilitate cell growth and produce fucosylactose at high purity, high yield and high productivity. The detailed technologies associated with fed-batch culture are well-known in the art and are not described herein.

Mode for Invention

[0036] Hereinafter, the present invention will be described in more detail with reference to the following examples, but the scope of the present invention is not limited to the examples, and includes variations and technical concepts equivalent thereto.

[0037] Meanwhile, only the effect when using Corynebacterium glutamicum as a host cell will be described below, but Corynebacterium glutamicum, Corynebacterium ammonia genes, Corynebacterium thermoaminogenes, Brevibacterium flavum and Brevibacterium lactofermentum are expected to have the same effect, because the transformation system can be equally applied thereto.

PRODUCTION EXAMPLE 1

Production of Recombinant Plasmids

[0038] Escherichia coli K-12 MG1655 and Corynebacterium glutamicum ATCC 13032 were used in order to produce plasmids and 2′-fucosyllactose (2′-FL), respectively.

[0039] In order to establish pFGW(Ps) plasmids, gmd-wcaG gene clusters were amplified through PCR reaction using two DNA primers, namely GW-F and GW-R, from the genomic DNAs of K-12 MG1655, E. Coli, the promoters of the Sod gene were amplified through PCR reaction using two DNA primers, namely Sod-F and Sod-R from the genomic DNA of Corynebacterium glutamicum ATCC 13032, and then PSod-Gmd-WcaG DNA fragments were synthesized through an overlapping PCR reaction using two DNA primers, namely Sod-F and GW-R.

[0040] In addition, the transcription termination sequence was amplified from the pXMJ19 plasmids through PCR reaction using two DNA primers, namely Ter-F and Ter-R, and a PSod-Gmd-WcaG-ter sequence was synthesized from the synthesized pSod-Gmd-WcaG and transcription termination sequence as templates through PCR reaction using DNA primers Sod-F and Ter-R, and was then inserted into the pCES208 plasmids cut by the restriction enzyme, BamHI, to establish pGW plasmids.

[0041] In addition, a Tuf gene promoter was amplified through PCR reaction using two DNA primers Tuf-F1 and Tuf-R1 from the genomic DNAs of Corynebacterium glutamicum ATCC 13032, and α-1,2-fucosyltransferase was amplified through PCR reaction using two DNA primers, FT(Ps)-F and FT(Ps)-R, from the synthesized α-1,2-fucosyltransferase derived from Pseudopedobacter saltans DSM 12145, and pTuf-FT (Ps) DNA fragments were synthesized through an overlapping PCR reaction using two primers Tuf-F and FT(Ps)-R. The pTuf-FT (Ps) DNA fragments were inserted into the established pGW plasmid by treating with restriction enzyme NotI to establish PFGW(Ps) plasmids.

[0042] Meanwhile, in order to establish pXIL plasmids, lacY genes were amplified through PCR reaction using two DNA primers, namely ilvC-lacY-F and lacY pX-R, from the genomic DNAs of K-12 MG1655, E. Coli, the promoters of the ilvC genes were amplified through PCR reaction using two DNA primers, namely pX-ilvC-F and ilvC-lacY-R, from the genomic DNA of Corynebacterium glutamicum ATCC 13032, and then pilvC-lacY DNA fragments were synthesized through an overlapping PCR reaction using two DNA primers, namely pX-ilvC-F and ilvC-lacY-R, and the pilvC-lacY fragments were inserted into the pX plasmid (pXMJ19) treated with restriction enzymes, Not I and EcoR I to establish pXIL plasmids.

[0043] Meanwhile, in order to establish pFGW(Hp) plasmids, the established pGW plasmids were used, and Tuf gene promoters were amplified through PCR reaction using two DNA primers, namely Tuf-F1 and Tuf-R2, from the genomic DNAs of Corynebacterium glutamicum ATCC 13032, α-1,2-fucosyltransferase was amplified through PCR reaction using two DNA primers, namely FT(Hp)-F and FT(Hp)-R from the Helicobacter pylori ATCC 700392-derived α-1,2-fucosyltransferase synthesized through codon optimization of Corynebacterium glutamicum, and then pTuf-FT(Ps) DNA fragments were synthesized through an overlapping PCR reaction using two DNA primers, namely Tuf-F1 and FT(Hp)-R. Then, the pTuf-FT(Ps) DNA fragments were inserted into the established pGW plasmid by treating the established pGW plasmid with restriction enzyme NotI to establish pFGW(Hp) plasmids.

[0044] Meanwhile, the strains, plasmids and nucleic acid and amino acid sequences used for the present Production Example are shown in Tables 1 to 4 below.

TABLE-US-00001 TABLE 1 Strains E. coli K-12 MG1655 F.sup.−, lambda.sup.−, rph-1 C. glutamicum Wild-type strain, ATCC13032

TABLE-US-00002 TABLE 2 Nucleic acid and amino acid sequences gmd nucleic acid sequence SEQ ID NO: 1 wcaG nucleic acid sequence SEQ ID NO: 2 lacY nucleic acid sequence SEQ ID NO: 3 FT(Ps) nucleic acid sequence SEQ ID NO: 4 FT(Ps) amino acid sequence SEQ ID NO: 5 FT(Hp) nucleic acid sequence SEQ ID NO: 6 FT(Hp) amino acid sequence SEQ ID NO: 7

TABLE-US-00003 TABLE 3 Primers primer Sequence (5′.fwdarw.3′) pX-ilvC-F GTCATATGATGGTCGCGGATCCGAATTCCCAGGCAAGCTCCGC ilvC-lacY-R GTTTTTTAAATAGTACATAATCTCGCCTTTCGTAAAAATTTTGGT ilvC-lacY-F TTACGAAAGGCGAGATTATGTACTATTTAAAAAACACAAACTTTTGGATGTT CGG lacY pX-R GCCTTTCGTTTTATTTGCTCGAGTGCGGCCGCTTAAGCGACTTCATTCACCTG ACGAC Tuf-F1 TGGAGCTCCACCGCGGTGGCTGGCCGTTACCCTGCGAA Tuf-R1 CAAATATCATTGTATGTCCTCCTGGACTTCG FT(ps)-F AGGACATACAATGATATTTGTAACCGGATATG FT(ps)-R CGCTTCACTAGTTCTAGAGCTTAAATAATGTGTCGAAACAGATTC Sod-F GCTCTAGAACTAGTGAAGCGCCTCATCAGCG Sod-R TACACCGGTGATGAGAGCGACTTTTGACATGGTAAAAAATCCTTTCGTAGGT TTCCGCAC GW-F ATGTCAAAAGTCGCTCTCATCACCGGTGTA GW-R CAAGCTGAATTCTTACCCCCGAAAGCGGTC ter-F GACCGCTTTCGGGGGTAAGAATTCAGCTTG ter-R GGTATCGATAAGCTTGATATCGAATTCCTGCAGCCCGGGGAAAAGGCCATCC GTCAGGAT Tuf-R2 TGAAAGCCATTGTATGTCCTCCTGGACTTCGT FT(Hp)-F GGACATACAATGGCTTTCAAGGTGGTCCAAAT FT(Hp)-R GCTTCACTAGTTCTAGAGCTTAAGCATTGTATTTCTGGCTCTTCACTTCG

TABLE-US-00004 TABLE 4 Plasmids Plasmid Related features Ref. pCES208 Km.sup.R, C. glutamicum/E. coli shuttle vector J. Microbiol. Biotechnol. (2008), 18(4), 639647 pXMJ19 Cm.sup.R, C. glutamicum/E. coli shuttle vector Biotechnology Techniques (1999), 13, 437441 pGW pCES208 + Sod-gmd-wcaG Present invention pFGW(Ps) pCES208 + Tuf-FT(Ps) + Sod-gmd-wcaG Present invention pFGW(Hp) pCES208 + Tuf-FT(Hp) + Sod-gmd-wcaG Present invention pXIL pXMJ19 + ilvC-lacY Present invention

EXAMPLE 1

Culture of Recombinant Strain Introduced with Fucosyltransferase Derived from Pseudopedobacter saltans

[0045] Corynebacterium glutamicum ATCC 13032 inserted with pFGW (Ps, FIG. 1) and pXIL (FIG. 2) was seed-cultured in a test tube containing 5 mL of BHI (brain heart infusion) medium supplemented with appropriate antibiotics (kanamycin 25 μg/mL and tetracycline 5 μg/mL) at 30° C. and 250 rpm for 12 hours. FIG. 1 is a schematic diagram showing a pFGW (Ps) plasmid, and FIG. 2 is a schematic diagram showing a pXIL plasmid.

[0046] Batch culture was carried out at 30° C. and at 250 rpm for 90 hours in a 250 mL flask containing 50 mL of minimum medium ((NH.sub.4).sub.2SO.sub.4 20 g/L, Urea 5 g/L, KH.sub.2 PO.sub.4 1 g/L, K.sub.2HPO.sub.4 1 g/L, MgSO.sub.4.7H.sub.2O 0.25 g/L, MOPS 42 g/L, CaCl.sub.2 10 mg/L, Biotin 0.2 mg/L, Protocatechuic acid 30 mg/L, FeSO.sub.4.7H.sub.2O 10 mg/L, MnSO.sub.4.H.sub.2O 10 mg/L, ZnSO.sub.4.7H.sub.2O 1 mg/L, CuSO.sub.4 0.2 mg/L, NiCl.sub.2.6H.sub.2O 0.02 mg/L, Glucose 40 g/L, Lactose 10 g/L, pH 7.0).

COMPARATIVE EXAMPLE 1

Culture of Recombinant Strain Introduced with Helicobacter pylori-Derived Fucosyltransferase

[0047] The same culture method was used in Example 1 except that pFGW (Ps, FIG. 1) was changed to pFGW (Hp, FIG. 3). FIG. 3 is a schematic diagram showing a pFGW (Hp) plasmid.

EXPERIMENTAL EXAMPLE 1

Comparison of 2′-FL Production of Recombinant Strains of Example 1 and Comparative Example 1

[0048] The production amounts of 2′-FL in the recombinant strains prepared in Example 1 and Comparative Example 1 were compared (FIG. 4, FIG. 5, Table 5). FIG. 4 shows the result of culture of the recombinant strain introduced with fucosyltransferase derived from Helicobacter pylori and

[0049] FIG. 5 shows the result of culture of the recombinant strain introduced with fucosyltransferase derived from Pseudopedobacter saltans (.circle-solid.: Dried cell weight, .square-solid.: Lactose, .Math.: Glucose, .diamond-solid.: 2′-FL, ⋄ Lactate, and ∘: Acetate).

TABLE-US-00005 TABLE 5 Derived from Final dried Maximum 2′-FL fucosyllactose cell weight concentration 2′-FL/dried Productivity Transferase (g/L) (mg/L) cell (mg/g) (mg/L/h) Helicobacter pylori 15.51 600 38.68 6.25 Pseudopedobacter 12.37 1,050 84.88 11.7 saltans

[0050] The experimental results showed that the recombinant strain introduced with fucosyltransferase derived from Pseudopedobacter saltans exhibited about twice the 2′-fucosyllactose productivity as the recombinant strain introduced with fucosyltransferase derived from Helicobacter pylori.