Streptomyces-sourced regulatory factor, regulatory factor interaction system, genetically engineered bacterium and application thereof

Abstract

The invention belongs to the technical field of genetic engineering and biosynthesis, and particularly relates to a regulatory factor derived from streptomyces, a regulatory factor interaction system, a genetically engineered bacterium and application of the genetically engineered bacterium. Specifically, the regulatory factors P1-A32 and P24-A32 provided by the invention both have a multi-effect regulation function, both show interaction activity with the ActVI-ORFA in vitro and have regulation targets overlapped with the ActVI-ORFA in vivo, and two groups of multi-effect regulation systems (ActVI-ORFA / P1-A32 and ActVI-ORFA / P24-A32) can be formed. In corresponding deletion bacteria, based on metabonomics analysis, the three regulatory factors (ActVI-ORFA, P1-A32 and P24-A32) are found to be capable of regulating the biosynthesis level of a plurality of natural products. The application of the compounds is expected to provide regulatory elements for mass production of natural active products, and the compounds have important value in industrial application and development of drugs.

Description

Technical Field

[0001] The present invention belongs to the technical field of genetic engineering and biosynthesis, and specifically relates to a regulatory factor derived from Streptomyces, a regulatory factor interaction system, a genetically engineered bacterium and applications thereof. Background Art

[0002] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention, and should not necessarily be regarded as an admission or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art.

[0003] Streptomyces has the potential to synthesize abundant active substances because their genome contains a large number of active substance biosynthesis gene clusters, and most of the gene clusters are silent. The synthesis process of active substances from Streptomyces is precisely controlled by signal molecules and regulatory factors inside and outside the cell. The metabolic-related regulatory system of Streptomyces is mainly divided into pathway-specific regulation (local regulation) and pleiotropic regulation (global regulation). Pathway-specific regulatory factors mainly exist in the biosynthesis gene clusters of active substances, directly regulating the expression of specific genes in specific pathways; pleiotropic regulatory factors are distributed in uncertain positions of the genome, and they control the synthesis of various natural products by Streptomyces through regulating pathway-specific regulatory factors, and can also control morphological development, so they constitute global regulation within the cell.

[0004] Pathway-specific regulatory factors in Streptomyces usually include at least two protein domains, one is the signal receiving domain (SRD), and the other is the DNA-binding domain (DBD). Pathway-specific regulatory factors can be divided into multiple subfamilies, such as Streptomyces Antibiotic Regulator Proteins (SARPs), TetR Family of Regulators (TRFs), LysR Family of Regulators, MarR Family of Regulators, LuxR Family of Regulators, etc.

[0005] Streptomyces coelicolor A3(2) is the first Streptomyces to complete genome sequencing and is the model species of the genus Streptomyces. The research on the synthesis mechanism and molecular regulatory network of natural active products of Streptomyces is based on Streptomyces coelicolor. Actinorhodin (ACT) belongs to the PNQ family of aromatic polyketide antibiotics (pyranonaphthoquinones, PNQ) ( Figure 1 ), is one of the many active substances produced by Streptomyces coelicolor, and is also a model compound for the biosynthesis and molecular regulation of polyketide natural products.

[0006] Many new regulatory genes in Streptomyces encode regulatory factors that are clearly involved in the synthesis and regulation of specific active natural products, but their mechanism of action has not yet been elucidated and they have no sequence homology with other regulatory proteins. This is the case with actVI-ORFA, a gene encoding a new regulatory factor in the actinomycin biosynthesis gene cluster, which can exert pleiotropic regulatory activities, and its homologous genes are widely present in the PNQ family gene cluster ( Figure 1 ). At the same time, identifying new regulatory factors in Streptomyces and revealing their new regulatory mechanisms will help develop new regulatory elements to activate a large number of silent gene clusters in Streptomyces, help construct high-yield antibiotic strains, and accelerate the development of new natural drugs from Streptomyces. Summary of the invention

[0007] In view of the deficiencies of the above-mentioned prior art, the inventors, after long-term technical and practical exploration, provide regulatory factors, regulatory factor interaction systems, genetically engineered bacteria and their applications derived from Streptomyces. Specifically, in the process of studying the regulation mechanism of actⅥ-ORFA, the present invention found that it can regulate the ability to synthesize multiple secondary metabolites, and at the same time identified the interacting protein P1-A32 (TerD family member) and the interacting protein P24-A32 (peptidyl arginine deaminase family member) of this regulatory factor, and constructed genetically engineered bacteria lacking these two regulatory factors to study their regulatory effects on the biosynthesis of natural active products of Streptomyces. Based on the above research results, the present invention is completed.

[0008] In order to achieve the above technical objectives, the present invention adopts the following technical solutions:

[0009] The first aspect of the present invention provides a regulatory factor, which is named P1-A32 or P24-A32;

[0010] in,

[0011] The P1-A32 has:

[0012] a1) the amino acid sequence shown in SEQ ID NO.4; or,

[0013] a2) an amino acid sequence having at least 90% sequence homology with SEQ ID NO.4.

[0014] The P1-A32 sequence is derived from Streptomyces coelicolor A3 (2), and its amino acid sequence consists of 395 amino acids. The encoded protein contains a TerD protein domain (the mechanism is unknown). Because it has an in vitro interaction relationship with the above-mentioned Act VI-ORFA, it is called the Act VI-ORFA interacting protein.

[0015] The P24-A32 has:

[0016] b1) the amino acid sequence shown in SEQ ID NO.6; or

[0017] b2) an amino acid sequence having at least 90% sequence homology with SEQ ID NO.6.

[0018] The P24-A32 is derived from Streptomyces coelicolor A3 (2), and its amino acid sequence consists of 340 amino acids. The encoded protein contains a peptidyl arginine deaminase protein domain. Because it interacts with the Act VI-ORFA described above, it is also called the Act VI-ORFA interacting protein.

[0019] The second aspect of the present invention provides a gene encoding the above-mentioned regulatory factor. The gene is named p1-A32 or p24-A32;

[0020] Wherein, the p1-A32 has:

[0021] c1) a nucleotide sequence as shown in SEQ ID NO.3; the gene sequence is derived from Streptomyces coelicolor A3 (2), and its nucleotide sequence consists of 1188 bases, encoding a regulatory factor with an unknown regulatory mechanism;

[0022] c2) a sequence formed by substitution, deletion and / or addition of one or more nucleotides of the nucleotide sequence as shown in c1);

[0023] c3) a nucleic acid molecule that has 50% or more identity with the nucleotide sequence defined in c1) or c2) and encodes the regulatory factor;

[0024] c4) A nucleotide sequence that can hybridize with the nucleotide sequence described in any one of c1) to c3) under stringent conditions and encodes the regulatory factor.

[0025] The p24-A32 has:

[0026] d1) a nucleotide sequence as shown in SEQ ID NO.5; the gene sequence is derived from Streptomyces coelicolor A3 (2), and its nucleotide sequence consists of 1020 bases, encoding a regulatory factor with an unknown regulatory mechanism;

[0027] d2) a sequence formed by substitution, deletion and / or addition of one or more nucleotides of the nucleotide sequence as shown in d1);

[0028] d3) a nucleic acid molecule that has 50% or more identity with the nucleotide sequence defined in d1) or d2) and encodes the regulatory factor;

[0029] d4) A nucleotide sequence that can hybridize with the nucleotide sequence described in any one of d1) to d3) under stringent conditions and encodes the regulatory factor.

[0030] The third aspect of the present invention provides a regulatory factor interaction system, which comprises the above-mentioned regulatory factor and ActVI-ORFA.

[0031] The present invention has found through research that ActVI-ORFA can interact with P1-A32 protein and P24-A32 protein in vitro, respectively, indicating the correlation of their functions, forming two groups of regulatory factor systems (ActVI-ORFA / P1-A32, ActVI-ORFA / P24-A32).

[0032] The Act VI-ORFA is derived from Streptomyces coelicolor A3 (2), and its nucleotide sequence is shown in SEQ ID NO.1, and its amino acid sequence is shown in SEQ ID NO.2.

[0033] Specifically, ActVI-ORFA is a novel regulatory factor identified from the genome of Streptomyces coelicolor A3(2), and its encoding gene actVI-ORFA is located in the actinomycetophthora biosynthesis gene cluster. Previous gene deletion studies have found that it has pleiotropic regulatory functions. The identified novel regulatory factor encoding genes p1-A32 and p24-A32 are located in the genome of Streptomyces coelicolor A3(2).

[0034] The wild strain containing the regulatory factor, Streptomyces coelicolor A3 (2), is an actinomycete that has the potential to produce a variety of natural active products, including actinomycin (ACT), undecylprodigiosin, germicidin, coelibactin, etc. It is a model strain for natural product research ( Figure 1 ).

[0035] The fourth aspect of the present invention provides a host bacterium, wherein the host bacterium contains an expression vector of the above-mentioned regulatory factor; the regulatory factor may also be ActVI-ORFA.

[0036] The expression vector may be a plasmid, specifically a pET28a plasmid.

[0037] The host bacteria may be prokaryotic bacteria, wherein the prokaryotic bacteria may be Escherichia coli, more specifically Escherichia coli BL21 (DE3).

[0038] More specifically, the present invention discloses a strain for expressing Act VI-ORFA protein, named BL21 / pET28a-ORFA, specifically, the pET28a plasmid carrying the act VI-ORFA gene is introduced into Escherichia coli BL21 (DE3).

[0039] The invention discloses a strain for expressing a P1-A32 protein, which is named BL21 / pET28a-P1-A32. Specifically, a pET28a plasmid carrying a p1-A32 gene is introduced into Escherichia coli BL21 (DE3).

[0040] The invention discloses a strain for expressing P24-A32 protein, which is named as BL21 / pET28a-P24-A32. Specifically, a pET28a plasmid carrying a p24-A32 gene is introduced into Escherichia coli BL21 (DE3).

[0041] A fifth aspect of the present invention provides a genetically engineered bacterium, wherein the genetically engineered bacterium is a strain lacking the above-mentioned regulatory factors.

[0042] Specifically, the present invention discloses an engineering bacterium for detecting the effect on the biosynthesis yield of compounds such as actinomycin, wherein the engineering bacterium is a p1-A32-deficient engineering bacterium named Streptomyces coelicolor A3(2)-ΔP1 A32 , which is based on Streptomyces coelicolor A3(2) with p1-A32 deleted.

[0043] The invention discloses an engineering bacterium for detecting the effect on the biosynthesis yield of compounds such as actinomycin, wherein the engineering bacterium is a p24-A32-deficient engineering bacterium named Streptomyces coelicolor A3(2)-ΔP24 A32 , which is based on Streptomyces coelicolor A3(2) with the p24-A32 deletion.

[0044] The sixth aspect of the present invention provides the use of the above-mentioned regulatory factors, genes, regulatory factor interaction systems, host bacteria and genetically engineered bacteria in any one or more of the following:

[0045] e1) Regulating the synthesis of natural active products;

[0046] e2) constructing regulatory factor engineering strains;

[0047] e3) Development of new natural medicines derived from Streptomyces.

[0048] Wherein, the natural active product includes but is not limited to actinomycin.

[0049] Compared with the existing technical solutions, the above one or more technical solutions have the following beneficial technical effects:

[0050] The above technical scheme identifies more new regulatory factors from Streptomyces, especially identifies more regulatory factors related to the biosynthesis of natural active products, completes the cloning and identification of the coding genes of these regulatory factors, studies their regulatory mechanisms, and constructs regulatory factor engineering strains, thereby helping to construct high-yield antibiotic strains, accelerate the development of new natural drugs derived from Streptomyces, and promote their application in antibiotic production. Therefore, it has good practical application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0052] Figure 1 : Structure and gene cluster of representative compounds of PNQ family and phylogenetic tree analysis of actVI-ORFA;

[0053] A: Actinorhodin and others belong to the PNQ antibiotic family and have similar nucleus structures;

[0054] B: The actinomycin gene cluster contains the small protein gene actⅥ-ORFA;

[0055] C: Systematic evolutionary analysis of actⅥ-ORFA and its homologous genes revealed that they may have regulatory functions.

[0056] Figure 2 :ActVI-ORFA, P1-A32, P24-A32 protein expression, purification and in vitro interaction detection;

[0057] A: The ActVI-ORFA, P1-A32, and P24-A32 encoding genes were inserted into the pET28a plasmid, respectively, and transformed into Escherichia coli BL21 (DE3) for expression and purification;

[0058] B: MST detected the interaction between ActⅥ-ORFA and P1-A32, with a Kd value of 206 nM;

[0059] C: MST detected the interaction between ActⅥ-ORFA and P24-A32, with a Kd value of 328nM;

[0060] Figure 3 : Comparison of actinomycin (ACT) accumulation after knockout of actⅥ-ORFA, p1-A32, and p24-A32;

[0061] A: Compared with the wild type of S. coelicolor A3(2), the deletion of actVI-ORFA resulted in decreased ACT production in plate assay;

[0062] B: After the liquid fermentation broth was treated with 1N NaOH, the absorbance at a wavelength of 640nm was detected. The detection showed that the deletion of actVI-ORFA led to a decrease in ACT production (ACT was blue under alkaline conditions), and the ACT production dropped to about 1 / 5 of the wild-type production;

[0063] C: Deletion of p1-A32 and p24-A32 resulted in decreased ACT production relative to the wild type of S. coelicolor A3(2).

[0064] Figure 4 : Comparison of the accumulation of each product after knockout of actⅥ-ORFA, p1-A32 and p24-A32 by LC-MS;

[0065] A: LC-MS detection of changes in the content of each product in the R4 medium fermentation extract after the deletion of act VI-ORFA;

[0066] B: Mass spectrum corresponding to the metabolic difference peaks in A (known compounds have been annotated);

[0067] C: LC-MS detection of changes in the content of each product in the fermentation extract of R4 medium after the deletion of p1-A32 and p24-A32;

[0068] D: Mass spectrum corresponding to the metabolic differential peaks in C (known compounds have been annotated).

[0069] Figure 5 : Omics analysis of three knockout strains (A3(2)-ΔORFA, A3(2)-ΔP1-A32, A3(2)-ΔP24-A32);

[0070] A: The number of targets with significant differential expression at the protein level (log2foldCharge>2 or log2foldCharge<-2, p-value<0.05);

[0071] B: Overlap analysis of targets regulated by P1-A32, P24-A32, and ActVI-ORA at the protein level;

[0072] C: Number of targets with significant differential expression at the transcriptional level (log2foldCharge>2 or log2foldCharge<-2, p-value<0.05);

[0073] D: Overlap analysis of targets regulated by P1-A32, P24-A32 and ActVI-ORA at the transcriptional level. DETAILED DESCRIPTION

[0074] It should be noted that the following detailed descriptions are illustrative and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0075] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0076] In the following examples, the materials and reagents used were obtained from commercial sources unless otherwise specified. The experimental methods described are conventional methods in the art unless otherwise specified.

[0077] Among them: Escherichia coli BW25113 (containing Red recombinase system), Escherichia coli ET12567 / pUZ8002, Escherichia coli BL21 (DE3), Streptomyces coelicolor A3 (2), and expression vector pET28a.

[0078] General description: Streptomyces coelicolor A3(2) is a model strain of Streptomyces, which can synthesize a variety of compounds such as actinomycin (among which actinomycin is a model compound of polyketide natural products); the gene encoding ActVI-ORFA, one of the regulatory factors described in the present invention, is present in the genome of Streptomyces coelicolor A3(2) (in the actinomycin biosynthesis gene cluster); the genes encoding the other two regulatory factors (P1-A32, P24-A32) are also located in the genome of Streptomyces coelicolor A3(2) (outside the actinomycin biosynthesis gene cluster);

[0079] Streptomyces culture medium is R4 medium, formula (per liter): casamino acid 0.1g, yeast extract 1g, glucose 10g, L-proline 3g, trace element solution 2ml, K2SO4 0.2g, MgCl2·6H2O 10g, TES 5.6g, CaCl2·2H2O4g, pH (adjusted with KOH) 7.2

[0080] Example 1: Expression and purification of ActVI-ORFA, P1-A32 and P24-A32 proteins and detection of interactions (1) Construction of ActVI-ORFA, P1-A32 and P24-A32 expression plasmids ActVI-ORFA, p1-A32 and p24-A32 sequences were amplified by PCR using total DNA from Streptomyces coelicolor A3 (2) as a template. The primer sequences are as follows:

[0081] ORFA-pET28a-F:

[0082] 5'-CCTGGTGCCGCGCGGCAGCCATATGATGACCATCACCGCGCTTCC-3'; ORFA-pET28a-R:

[0083] 5'-GGTGGTGGTTGCTCGAGTGCGGCCGCTCAGGCCGGGAAGACGTGGT-3'. P1-A32-pET28a-F:

[0084] 5'-CCTGGTGCCGCGCGGCAGCCATATGATGACGCAGATGACGAAGGG-3'P1-A32-pET28a-R:

[0085] 5'-GGTGGTGGTGCTCGAGTGCGGCCGCTCAGCCGCCCACCCCGAGCC-3'P24-A32-pET28a-F:

[0086] 5'-CCTGGTGCCGCGCGGCAGCCATATGATGACCTTCCGCATGCCGCC-3'

[0087] P24-A32-pET28a-R:

[0088] 5'-GGTGGTGGTTGCTCGAGTGCGGCCGCCTAGGTCCTCGGCTGTTGCT-3'

[0089] (2) The obtained PCR fragments were recombined with the linearized pET28a plasmid (the expression plasmid construction process was carried out in Escherichia coli BW25113 (containing the Red recombinase system)), and then transformed into Escherichia coli BL21 (DE3) for protein expression and purification.

[0090] (3) The protein ActVI-ORFA was subjected to MST detection with P1-A32 and P24-A32 respectively. The experimental results showed that ActVI-ORFA interacted with both P1-A32 and P24-A32 ( Figure 2). Example 2: Construction of p1-A32 and p24-A32 single gene deletion engineered bacteria, solid fermentation to compare the accumulation of actinomycetophthrin products, liquid fermentation to compare the changes in the synthesis yield of various metabolites (1) Design PCR primers, the sequences are as follows:

[0091] P1-A32-LA-F:

[0092] 5'-GCCCTGAGTGCTTGCGGCAGCGTGAAGCTTCGCCGATCAGGTTGAGCT GC-3'

[0093] P1-A32-LA-R:5'-CGTCATCTGCGTCATGGCGT-3'

[0094] P1-A32-RA-F:

[0095] 5'-TGTGAAGATCACGCCATGACGCAGATGACGTGAGGCTCAGTCCCGGCG CA-3'

[0096] P1-A32-RA-R:

[0097] 5'-CGGAAAAGATCCGTCGACCTGCAGGCATGCGGCGGATGGCGAAGGAG GTG-3'

[0098] The genomic DNA of Streptomyces coelicolor A3 (2) was used as a template and PCR amplification (30 cycles: 1 min at 94°C, 60 s at 60°C and 2 min at 72°C) was performed to obtain a PCR product containing 2 kb homologous fragments on both sides of the upstream and downstream of the p1-A32 gene;

[0099] (2) Design primers with the following sequences:

[0100] P24-A32-LA-F:

[0101] 5'-GCCCTGAGTGCTTGCGGCAGCGTGAAGCTTACCAACACCGCGACCGTG CC-3'

[0102] P24-A32-LA-R:

[0103] 5'-TGTCCACTCCCGGGTCTTCTAGGTCCTCGGGGAGATGTCCAGGGGGTC GG-3'

[0104] P24-A32-RA-F:5'-CCGAGGACCTAGAAGACCCG-3'

[0105] P24-A32-RA-R:

[0106] 5'-CGGAAAAGATCCGTCGACCTGCAGGCATGCCCGAGCTCCTTGCCCTTC AG-3'

[0107] The genomic DNA of Streptomyces coelicolor A3 (2) was used as a template and PCR amplification (30 cycles: 1 min at 94°C, 60 s at 60°C and 2 min at 72°C) was performed to obtain a PCR product containing 2 kb homologous fragments on both sides of the upstream and downstream of the p24-A32 gene;

[0108] (3) The PCR products obtained in (1) and (2) were recombined with the pYH7 plasmid linearized with HindIII (the construction process was carried out in Escherichia coli BW25113 (containing the Red recombinase system)), and the suicide plasmids constructed were transformed into Streptomyces coelicolor A3 (2) by conjugation transfer;

[0109] (4) Single gene deletion mutants of P1-A32 and P24A32 were obtained by relaxed culture and colony PCR screening and named A3(2)-ΔP1-A32 and A3(2)-ΔP24-A32;

[0110] (5) The results of solid culture test in R4 medium, alkali treatment, and LC / MS test of R4 medium liquid fermentation broth showed that compared with the wild-type strain A3(2), the production of actinomycin in A3(2)-ΔP1-A32 and A3(2)-ΔP24-A32 decreased (indicated by the blue color of the plate); LC / MS test also showed that the production of other compounds also changed significantly ( Figure 3-4 ).

[0111] Example 3: Solid fermentation experiment to compare the accumulation of actinomycin products after knockout of actVI-ORFA, and liquid fermentation analysis of the effects on the synthesis of various metabolites

[0112] (1) Cultivate and verify the ActVI-ORAF deletion strain A3(2)-ΔORFA obtained in previous studies in R4 liquid medium (Li C, Li Le, Huang L, Li A. Pleiotropic effects of ActVI-ORFA as an unusual regulatory factor identified in the biosynthetic pathway of actinorhodin in Streptomyces coelicolor. Microbiological Research, 2021, 250: 126792);

[0113] (2) The results of R4 plate assay, alkali treatment, and HPLC assay of R4 fermentation broth showed that the production of actinomycin in A3(2)-ΔORFA decreased to 1 / 5 of the original content compared with the wild-type strain A3(2). LC / MS assay also showed that the production of other compounds also changed ( Figure 3-4 ).

[0114] Example 4: Proteomic and transcriptomic analysis of Act VI-ORFA and interacting protein knockout bacteria

[0115] (1) A3(2) (wild bacteria) and three mutants (A32-ΔORFA, A32-ΔP1-A32, A32-ΔP24-A32) were fermented in R4 liquid medium for 4 days;

[0116] (2) After bacterial collection, they were sent to Beijing Novogene Technology Co., Ltd. for transcriptomics and proteomics sequencing;

[0117] (3) Transcriptomics and proteomics data analysis showed that P1-A32 and P24-A32 and ActVI-ORFA can regulate multiple targets, and the targets regulated by each other overlap to a certain extent, indicating that their regulatory functions interact and jointly regulate the expression of downstream target genes ( Figure 5 ).

[0118] Table 1 Gene sequences and protein sequences involved in the present invention

[0119]

[0120]

[0121]

[0122]

[0123]

[0124] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A regulatory factor, characterized in that The regulatory factor is named P1-A32 or P24-A32; in, The P1-A32 has: a1) the amino acid sequence shown in SEQ ID NO.4; or, a2) an amino acid sequence having at least 90% sequence homology with SEQ ID NO.4; The P24-A32 has: b1) the amino acid sequence shown in SEQ ID NO.6; or b2) an amino acid sequence having at least 90% sequence homology with SEQ ID NO.

6.

2. A gene, characterized in that The gene encodes the regulatory factor according to claim 1.

3. The gene according to claim 2, characterized in that The gene is named p1-A32 or p24-A32; Wherein, the p1-A32 has: c1) the nucleotide sequence shown in SEQ ID NO.3; c2) a sequence formed by substitution, deletion and / or addition of one or more nucleotides of the nucleotide sequence as shown in c1); c3) a nucleic acid molecule that has 50% or more identity with the nucleotide sequence defined in c1) or c2) and encodes the regulatory factor; c4) a nucleotide sequence that can hybridize with the nucleotide sequence described in any one of c1) to c3) under stringent conditions and encodes the regulatory factor; The p24-A32 has: d1) the nucleotide sequence shown in SEQ ID NO.5; d2) a sequence formed by substitution, deletion and / or addition of one or more nucleotides of the nucleotide sequence as shown in d1); d3) a nucleic acid molecule that has 50% or more identity with the nucleotide sequence defined in d1) or d2) and encodes the regulatory factor; d4) A nucleotide sequence that can hybridize with the nucleotide sequence described in any one of d1) to d3) under stringent conditions and encodes the regulatory factor.

4. A regulatory factor interaction system, characterized in that: The regulatory factor interaction system comprises the regulatory factor described in claim 1 and ActVI-ORFA.

5. A host bacterium, characterized in that The host bacteria contains the expression vector of the regulatory factor according to claim 1.

6. The host bacteria according to claim 5, characterized in that The regulatory factor also includes ActVI-ORFA; the expression vector is a plasmid, and is further specifically a pET28a plasmid.

7. The host bacteria according to claim 5, characterized in that The host bacteria is a prokaryotic bacterium, and the prokaryotic bacterium is Escherichia coli.

8. A genetically engineered bacterium, characterized in that: The genetically engineered bacteria are strains lacking the regulatory factors described in claim 1.

9. Use of the regulatory factor according to claim 1, the gene according to any one of claims 2-3, the regulatory factor interaction system according to claim 4, the host bacteria according to any one of claims 5-7, and the genetically engineered bacteria according to claim 8 in any one or more of the following: e1) Regulating the synthesis of natural active products; e2) constructing regulatory factor engineering strains; e3) Development of new natural medicines derived from Streptomyces.

10. The use according to claim 9, characterized in that: The natural active products include multiple different types of natural products including actinomycin.

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