The invention content is as follows:
one of the objectives of the present invention is to provide a Streptomyces marinus (Streptomyces sp.) SCSIO 15077 capable of producing tunicamycin E, which is deposited in the common microorganism center of the china committee for culture collection of microorganisms (CGMCC) at 23 months 1 in 2017, with the address: the collection number of the microbial research institute of the Chinese academy of sciences, No. 3 Xilu-Beijing province, Chaoyang, and the collection number is: CGMCC No. 13649.
The invention also provides a tunicamycin E which is a novel tunicamycin compound shown in a formula (I):
the invention also aims to provide application of Streptomyces sp SCSIO 15077 in preparation of tunicamycin E.
The fourth purpose of the invention is to provide a preparation method of tunicamycin E, wherein the tunicamycin E is prepared from a fermentation culture of Streptomyces sp SCSIO 15077.
According to the invention, the tunicamycin E is preferably prepared from a fermentation culture of Streptomyces sp SCSIO 15077, and specifically comprises the following steps:
(a) preparing a fermentation culture of Streptomyces marinus (Streptomyces sp.) SCSIO 15077, separating fermentation supernatant and mycelium of the fermentation culture, extracting the fermentation supernatant with butanone, concentrating butanone phase to obtain extract A, soaking and extracting mycelium with acetone, and concentrating acetone leaching liquor to obtain extract B;
(b) and combining the extract A and the extract B, performing silica gel column chromatography by using chloroform-methanol as an eluent in a volume ratio of 100: 0. 95: 5. 9: 1. 8: 2. 5: 5. 0:100, performing gradient elution, and collecting chloroform-methanol with the volume ratio of 5: 5. 0: fractions Fr.5 and Fr.6 eluted at 100, and fractions Fr.5 and Fr.6 were purified to obtain tunicamycin E.
The fermentation culture for preparing the marine Streptomyces sp SCSIO 15077 is prepared by the following method:
inoculating Streptomyces marinus (Streptomyces sp.) SCSIO 15077 into a seed culture medium, fermenting to obtain a seed culture solution, inoculating the seed culture solution into a fermentation culture medium, and fermenting to obtain a fermentation culture, wherein the seed culture medium and the fermentation culture medium are both prepared from the following formula: 4g/L of glucose, 4g/L of yeast extract, 10g/L of malt extract powder, 30g/L of sea salt and the balance of water.
The fifth purpose of the invention is to provide the application of tunicamycin E in preparing antibacterial drugs.
An antibacterial agent characterized by containing an effective amount of the aforementioned tunicamycin E as an active ingredient.
Preferably, the antibacterial drug is a drug against bacillus thuringiensis or candida albicans.
The invention provides a marine Streptomyces sp (Streptomyces sp) SCSIO 15077 capable of producing tunicamycin antibiotics, and a new compound tunicamycin E can be prepared by using the strain, so that a biological preparation method is provided for the production and preparation of tunicamycin, and the strain has a wide application prospect.
The Streptomyces (Streptomyces sp.) SCSIO 15077 is deposited in the common microorganism center of the china committee for culture collection management (CGMCC) in 2017 at 1 month 23, and the address: the collection number of the microbial research institute of the Chinese academy of sciences, No. 3 Xilu-Beijing province, Chaoyang, and the collection number is: CGMCC No. 13649.
The specific implementation mode is as follows:
the following examples are further illustrative of the present invention and are not intended to be limiting thereof.
Example 1: isolation and identification of Streptomyces maritima (Streptomyces sp.) SCSIO 15077
The marine Streptomyces (Streptomyces sp.) SCSIO 15077 is separated from sediment samples with the water depth of-3536 m in the north of the south sea of China.
The taxonomical characteristics of the strain are as follows:
1. morphological characteristics:
the bacterial colony is dry, the single bacterial colony is generally round, smaller, more compact, not easy to diffuse, the middle is convex, the substrate hypha and the aerial hypha are combined closely and not easy to pick up, and the spores are easy to scrape after the spores are produced at the end stage. White aerial hyphae and yellow matrix hyphae were formed on ISP-4 medium (shown in FIG. 1).
2. Molecular biology separation characteristics:
the genomic DNA of the above isolated strain was extracted, and its 16S rDNA sequence (the nucleotide sequence of which is shown in SEQ ID NO. 1) was PCR-amplified by a conventional method, and sequencing analysis was performed to construct a phylogenetic tree based on the 16S rDNA sequence (shown in FIG. 2), indicating that the sequence similarity of the strain SCSIO S15077 and Streptomyces xinghaiensis S187(CP023202.1)16S rDNA was 99%, indicating that the strain SCSIO S15077 belongs to Streptomyces (Streptomyces xinghaiensis).
In summary, the strain SCSIO S15077 is identified as belonging to a species of Streptomyces, named as Streptomyces sp SCSIO 15077, which was deposited in the china general microbiological culture collection center (CGMCC) on 23/1/2017 at the address: the collection number of the microbial research institute of the Chinese academy of sciences, No. 3 Xilu-Beijing province, Chaoyang, and the collection number is: CGMCC No. 13649.
Example 2: separation and identification of tunicamycin E
1. Preparation of a fermentation culture of marine Streptomyces (Streptomyces sp.) SCSIO 15077:
(1) preparing a seed culture medium and a fermentation culture medium:
a) preparing a seed culture medium: each liter of the seed culture medium contains 4g of glucose, 4g of yeast extract, 10g of malt extract powder, 30g of sea salt and the balance of tap water, and the components are uniformly mixed and the pH value is adjusted to 7.0. 1L of seed culture medium is prepared, then evenly distributed in 20 conical flasks of 250mL, each flask is filled with 50mL of seed culture medium, and sterilized for 30min at 121 ℃ for later use.
b) Preparation of a fermentation medium: each liter of fermentation medium contains 4g of glucose, 4g of yeast extract, 10g of malt extract powder, 30g of sea salt and the balance of tap water, and the components are uniformly mixed and the pH value is adjusted to 7.0. Preparing 1L of fermentation medium, uniformly distributing into 5 1L conical flasks, and sterilizing at 121 deg.C for 30 min.
(2) Culturing seeds:
activated Streptomyces marinus (Streptomyces sp.) SCSIO 15077 (preservation number: CGMCC No.13649) was inoculated into a 250mL conical flask containing 50mL of seed medium, and cultured on a shaker at 28 ℃ and 200rpm for 24 hours to obtain a seed culture solution.
(3) Large-scale fermentation culture:
transferring 50mL of seed culture solution in the conical flask into a 1L conical flask filled with 200mL of fermentation medium, and culturing for 7 days on a shaking table at 28 ℃ and 200r/min to obtain a fermentation culture of Streptomyces marinus (Streptomyces sp.) SCSIO 15077.
2. Isolation of tunicamycin E from Streptomyces sp SCSIO 15077
(1) Extraction of fermentation cultures
Centrifuging a fermentation culture of Streptomyces sp SCSIO 15077 (3800-4000 r/min, 10-15 min) to separate a fermentation supernatant from mycelia; performing isovolumetric extraction on the fermentation supernatant for 3 times by using butanone, and performing rotary evaporation, condensation and concentration on a butanone phase to obtain an extract A; soaking and extracting the mycelium with acetone (2L), performing ultrasonic treatment to obtain acetone extract, and performing rotary evaporation, condensation and concentration on the acetone extract to obtain extract B.
(2) Extraction of tunicamycin E
And (3) analyzing by HPLC, wherein the components of the extract A and the extract B are similar, combining the extract A and the extract B, performing normal-phase silica gel column chromatography, using chloroform-methanol as a mobile phase, and performing separation according to the volume ratio of 100: 0. 95: 5. 9: 1. 8: 2. 5: 5. 0:100, and the fraction eluted with a 100% chloroform gradient is designated as fr.1, the chloroform-methanol volume ratio is 95: the fraction eluted with a gradient of 5 was designated as Fr.2, the chloroform-methanol volume ratio was 9: the fraction eluted with a gradient of 1 is designated as Fr.3, the chloroform-methanol volume ratio is 8: the fraction eluted with a gradient of 2 was designated as Fr.4, the chloroform-methanol volume ratio was 5: the fraction eluted with a gradient of 5 was designated as Fr.5, the chloroform-methanol volume ratio was 0: the fraction eluted at a gradient of 100 was designated Fr.6.
The fractions Fr.1 to 6 were analyzed by HPLC, and it was found that the fractions Fr.5 and Fr.6 contained tunicamycin E, and the combined fractions Fr.5 and Fr.6 were separated and purified by reversed-phase ODS (YMC-Pack ODS-A column, 250X 20mm,5 μm) semi-preparative HPLC (mobile phase CH)3CN/H2Isocratic elution with O50% v/v for 30min at a flow rate of 2.5mL/min (as shown in FIG. 3) gave 10mg of Compound 1 (retention time 15.8min), i.e., tunicamycin E.
(3) Identification of tunicamycin E
Through structural analysis, the identification results of the compound 1 prepared from the fermentation culture of Streptomyces marinus (Streptomyces sp.) SCSIO 15077 according to the present invention are as follows:
compound 1 is white powder, formula C37H60N4O16,HR-ESI-MS m/z 839.3895([M+Na]+);[α]25 D+43.3(c 0.07,MeOH);UV(MeOH)λmax(logε)206.00(3.88),259.40(3.98)nm;IR(film)vmax3308,2924,2853,1665,1551,1466,1377,1260,1092,1023cm-1. In one-dimensional NMR, 3 methyl signals (. delta.) are suggestedC22.8,C-8”;δC22.4,C-11”';δC13.9, C-14 "'); 10 methylene letter (. delta.)C35.3,C-6';δC60.5,C-6”;δC31.2,C-4”';δC27.8,C-5”';δC29.0-28.6,C-6”',C-7”',C-8”';δC38.4,C-9”';δC22.0,C-12”';δC31.2, C-13 "'); 16 methines; 4 olefin carbon signals (. delta.)C102.1,C-5;δC140.3,C-6;δC124.7,C-2”';δC142.4, C-3') and 4 carbonyl carbon signals (. delta.))C150.8,C-2;δC163.0,C-4;δC169.2,C-7”;δC166.1,C-1”')。1High field in H NMR spectrumOf two fatty chainsH0.79(3H, m, Me-11') and ΔH0.81(3H, m, Me-14 '), correlation of H-14' with C-9 ', C-10' and C-12 'by HMBC H-11', and combination of H-14 'with C-12' and C-131H-1The correlation of H-9 '/H-10 '/H-11 ' and H-10 '/H-12'/H-13'/H-14' in H COSY finally determines the signal deltaH0.87 methyl at C-10 "'. Review of the literature, NMR data of Compound 1 and literature [ Myers A G, Gin D Y, Rogers D H. ChemInform Abstract: Synthetic students of the diagnostic of (+) -diagnostic of viral-viral, and 5' -epi-viral-V [ J].Cheminform,1994,25(46).]The comparison of the reported NMR data of tunicamycin identifies that the compound 1 is a novel tunicamycin antibiotic, namely tunicamycin E, the structure of which is shown in a formula (I), and the data of a carbon spectrum and a hydrogen spectrum are shown in a table 1:
TABLE 1 NMR and Hydrogen spectra data for tunicamycin E
aMeasured in DMSO-d6.
After the crude extract is tested by a filter paper bacteriostatic ring method, the compound 1 is found to have certain bacteriostatic activity on most gram-positive bacteria and candida albicans. Selecting Bacillus thuringiensis BT01(Bacillus thuringiensis), Bacillus thuringiensis W102(Bacillus thuringiensis) and Candida albicans ATCC 96901(Candida albicans) with larger inhibition zone and good activity, and measuring the minimum inhibition concentration by a 96-well plate method by using Candida 98001(Candida albicans). The Minimum Inhibitory Concentration (MIC) of the compound 1 to two strains of Bacillus thuringiensis (Bacillus thuringiensis) is 0.5 and 2.0 mu g/mL, which is superior to the positive control of kanamycin and ampicillin. MICs for two Candida albicans strains (Candida albicans) were 8.0 and 32. mu.g/mL, respectively. The test results are shown in table 2.
TABLE 2 MIC values (μ g/mL) for Compound 1
a Bacillus thuringiensis BT01.b Bacillus thuringiensis W102.c Candida albicans ATCC 96901.d Candida albicans CMCC(F)98001.e These compounds were used as positive controls.
Sequence listing
<110> Nanhai ocean institute of Chinese academy of sciences
<120> marine streptomycete and tunicamycin compound and preparation method thereof
<160> 1
<170> SIPOSequenceListing 1.0
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<211> 1407
<212> DNA
<213> Streptomyces SCSIO 15077(Streptomyces sp. SCSIO 15077)
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gcttaccatg cagtcgaacg atgaacctct tcggagggga ttagtggcga acgggtgagt 60
aacacgtggg caatctgccc tgcactctgg gacaagccct ggaaacgggg tctaataccg 120
gatacgacca tctcgggcat ccgatggtgg tggaaagctc cggcggtgca ggatgagccc 180
gcggcctatc agcttgttgg tggggtgatg gcctaccaag gcgacgacgg gtagccggcc 240
tgagagggcg accggccaca ctgggactga gacacggccc agactcctac gggaggcagc 300
agtggggaat attgcacaat gggcggaagc ctgatgcagc gacgccgcgt gagggatgac 360
ggccttcggg ttgtaaacct ctttcagcag ggaagaagcg tgagtgacgg tacctgcaga 420
agaagcaccg gctaactacg tgccagcagc cgcggtaata cgtagggtgc gagcgttgtc 480
cggaattatt gggcgtaaag agctcgtagg cggcttgtcg cgtcggatgt gaaagcccgg 540
ggcttaaccc cgggtctgca ttcgatacgg gcaggctaga gttcggtagg ggagatcgga 600
attcctggtg tagcggtgaa atgcgcagat atcaggagga acaccggtgg cgaaggcgga 660
tctctgggcc gatactgacg ctgaggagcg aaagcgtggg gagcgaacag gattagatac 720
cctggtagtc cacgccgtaa acgttgggaa ctaggtgtgg gcgacattcc acgtcgtccg 780
tgccgcagct aacgcattaa gttccccgcc tggggagtac ggccgcaagg ctaaaactca 840
aaggaattga cgggggcccg cacaagcggc ggagcatgtg gcttaattcg acgcaacgcg 900
aagaacctta ccaaggcttg acatacaccg gaaagccgta gagatacggt cccccttgtg 960
gtcggtgtac aggtggtgca tggctgtcgt cagctcgtgt cgtgagatgt tgggttaagt 1020
cccgcaacga gcgcaaccct tgttctgtgt tgccagcatg cctttcgggg tgatggggac 1080
tcacaggaga ctgccggggt caactcggag gaaggtgggg acgacgtcaa gtcatcatgc 1140
cccttatgtc ttgggctgca cacgtgctac aatggccggt acaatgagct gcgataccgt 1200
gaggtggagc gaatctcaaa aagccggtct cagttcggat tggggtctgc aactcgaccc 1260
catgaagtcg gagtcgctag taatcgcaga tcagcattgc tgcggtgaat acgttcccgg 1320
gccttgtaca caccgcccgt cacgtcacga aagtcggtaa cacccgaagc cggtggccca 1380
acccgtgagg gagggaatcg tcgaagt 1407