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Open AccessCommunication

Genome Sequencing of Streptomyces olivaceus SCSIO T05 and Activated Production of Lobophorin CR4 via Metabolic Engineering and Genome Mining

1
CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, RNAM Center for Marine Microbiology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou 510301, China
2
College of Oceanology, University of Chinese Academy of Sciences, 19 Yuquan Road, Beijing 100049, China
*
Author to whom correspondence should be addressed.
Mar. Drugs 2019, 17(10), 593; https://doi.org/10.3390/md17100593
Received: 18 September 2019 / Revised: 12 October 2019 / Accepted: 16 October 2019 / Published: 20 October 2019
(This article belongs to the Special Issue Bioactive Marine Heterocyclic Compounds)

Abstract

Marine-sourced actinomycete genus Streptomyces continues to be an important source of new natural products. Here we report the complete genome sequence of deep-sea-derived Streptomyces olivaceus SCSIO T05, harboring 37 putative biosynthetic gene clusters (BGCs). A cryptic BGC for type I polyketides was activated by metabolic engineering methods, enabling the discovery of a known compound, lobophorin CR4 (1). Genome mining yielded a putative lobophorin BGC (lbp) that missed the functional FAD-dependent oxidoreductase to generate the d-kijanose, leading to the production of lobophorin CR4 without the attachment of d-kijanose to C17-OH. Using the gene-disruption method, we confirmed that the lbp BGC accounts for lobophorin biosynthesis. We conclude that metabolic engineering and genome mining provide an effective approach to activate cryptic BGCs.
Keywords: genome sequencing; gene disruption; lobophorin; metabolic engineering; genome mining genome sequencing; gene disruption; lobophorin; metabolic engineering; genome mining

1. Introduction

Microbially produced natural products (NPs) are an important reservoir of therapeutic and agricultural agents [1]. In the previous years, quantities of new bioactive NPs were isolated from marine-derived Streptomyces strains, suggesting marine-derived Streptomyces as a predominant source of new NPs [2]. In recent years, whole-genome sequencing programs have made it clear that microorganisms have greater biosynthetic potential but are mostly underexplored by virtue that most biosynthetic gene clusters (BGCs) in a single microbial genome are normally silent. Activation of these silent BGCs contributes to new NPs discoveries. Zhang and co-workers activated a cryptic polycyclic tetramate macrolactam (PTM) BGC in Streptomyces pactum SCSIO 02999 by promoter engineering and heterologous expression [3], and also promoted the expression of a silent PKS/NRPS hybrid BGC in the same Streptomyces strain by the alteration of several regulatory genes [4]. The production of nocardamine [5] and atratumycin [6] in Streptomyces atratus SCSIO ZH16 was turned on via metabolic engineering. These genome-based studies exemplify the benefits of genome mining and metabolic engineering used for activating cryptic BGCs and discovering new bioactive NPs.
Lobophorins (Supporting Information (SI), Figure S1) belonging to a large class of spirotetronate antibiotics structurally feature a tetronate moiety spiro-linked with a cyclohexene ring, which is called pentacyclic aglycon or kijanolide [7,8,9,10,11,12,13,14,15,16,17]. Almost all of this class of compounds has a broad spectrum of antibacterial activities, as well as antitumor activity. Efforts to produce more spirotetronate antibiotics for drug discovery have thrived. Owing to the structural complexity of this family member, biosynthesis seems to be an effective way to afford the production of spirotetronate antibiotics, providing access to new analogues by pathway engineering and combinatorial biosynthetic approaches. In this paper, we report (i) the complete genome sequence of a deep-sea-derived Streptomyces olivaceus SCSIO T05, a talented strain capable of producing an array of putative NPs; (ii) activation of a cryptic lobophorin BGC (lbp) by mutagenetic methods and isolation of one known spirotetronate antibiotic lobophorin CR4 (1); and (iii) identification of the lbp BGC housed in S. olivaceus SCSIO T05 by gene-disruption experiment and bioinformatics analysis.

2. Results and Discussion

2.1. Genome Sequencing and Annotation of Streptomyces olivaceus SCSIO T05

Whole genome sequence is important when analyzing the potential production of secondary metabolites [5,18]. S. olivaceus SCSIO T05, a marine-derived strain, was previously reported to be isolated from the Indian Ocean deep-sea-derived sediment [19]. Its draft genome sequence was first gained by Illumina sequencing technology, but with several gap regions. In order to estimate the biosynthetic potential of S. olivaceus SCSIO T05, the complete genome was re-sequenced and acquired by the single-molecule real-time (SMRT) sequencing technology (PacBio). A total of 67156 filtered reads with high-quality data of 432570025 bp were generated, and then they were assembled into a linear contig by the hierarchical genome assembly process (HGAP) [20]. The complete genome revealed that 8458055 base pairs constitute a linear chromosome without a plasmid, with 72.51% of GC content (Figure 1 and Table 1). Totally, 7700 protein-coding genes were predicted, along with 18 rRNA and 65 tRNA. The genome sequence of S. olivaceus SCSIO T05 was deposited in GenBank (CP043317).
AntiSMASH analysis by using antiSMASH 5.0 [21] suggested 37 BGCs within the S. olivaceus SCSIO T05 genome (Figure 1 and Table 2). The 37 BGCs totally occupy 1.59 Mb, 18.76% of the complete genome. Most of the BGCs distribute in the two subtelomeric regions of the genome of some Streptomyces strains [18] and so do the BGCs in S. olivaceus SCSIO T05 genome. It is predicted that several BGCs are responsible for the production of polyketide- and nonribosome-peptide-derived secondary metabolites, including four PKS (Type I, Type II and Type III) and six NRPS, and six hybrid BGCs possess genes encoding more than one type of scaffold-synthesizing enzyme. Twenty-one BGCs are predicted to produce terpene, bacteriocin, lanthipeptide, or other categories. This analysis indicates that S. olivaceus SCSIO T05 is capable of producing an array of secondary metabolites, serving as a target strain for further metabolic engineering and genome mining.

2.2. Activation of a Cryptic Lobophorin BGC in the Genetically Engineered Mutant

In actuality, only a minority of potential chemicals are produced under standard laboratory culture conditions. Furthermore, the corresponding products are likely to be overlooked for multiple reasons, including low production rates, a large metabolic background, or improper culture conditions [22]. Fermented using modified-RA medium, the secondary metabolites produced by S. olivaceus SCSIO T05 were subsequently profiled using HPLC-DAD-UV. Multiple peaks were detected in the fermentation extract (Figure 2, trace i). We previously reported that five known NPs, rishirilides B (2) and C (3), lupinacidin A (4), galvaquinone B (5), and xiamycin A (6), were produced as major secondary metabolites from the wild-type strain [19,23]. In addition, an orphan dibenzoxazepinone biosynthetic pathway was mutagenically activated, leading to the production of new mycemycins [24], suggesting that S. olivaceus SCSIO T05 has a great potential for producing new NPs.
For exploring other secondary metabolites from the strain, S. olivaceus SCSIO T05/ΔrsdK2 (S. olivaceus SCSIO T05R) was constructed to abolish the production of the anthracenes [19]. The production of the second major secondary metabolites xiamycins was accumulated, along with a new peak around 26 min, distinct from the UV absorption characteristics of xiamycins (Figure 2, trace ii). For further background elimination of xiamycins, a “double-deletion” mutant S. olivaceus SCSIO T05/ΔrsdK2xmcP (S. olivaceus SCSIO T05RX) was constructed [23] in which the new peak (1) appeared to be the major product (Figure 2, trace iii). Accordingly, the S. olivaceus SCSIO T05RX mutant was fermented at a large scale, enabling the isolation and structure elucidation of this newly generated compound. It was identified as a known compound designated as lobophorin CR4 (Figure 3), by comparing HRESIMS, 1H, and 13C NMR data (SI, Figures S2–S4) to the reported data of an intermediate isolated from the Streptomyces sp. SCSIO 01127/ΔlobG1 mutant [11]. It is reported that shifting metabolic flux of a wild-type strain by blocking the predominant product pathways may afford new secondary metabolites [5]. During our efforts to acquire new secondary metabolites by shifting the metabolic flux of marine actinomycetes [5,23,24], the production of nocardamine, olimycins, and mycemycins was turned on at the expense of major products by using gene knock-out methods. Similarly, the “double-deletion” mutant (S. olivaceus SCSIO T05RX) was constructed to abolish the production of two major secondary metabolites, anthracenes and xiamycins, from the wild-type strain [19,23]. With the engineered shifting of S. olivaceus metabolic flux, the newly produced lobophorin CR4 was activated.

2.3. Identification of a Putative Lobophorin (lbp) BGC via Genome Mining

The antiSMASH analysis of the complete genome of S. olivaceus SCSIO T05 revealed a 99.1 kb type I PKS BGC named as lobophorin BGC (lbp), showing highly similar traits to the reported lob BGCs from Streptomyces sp. FXJ7.023 [16] and Streptomyces sp. SCSIO 01127 [11]. The complete lbp contains 38 open reading frames (ORFs). The genetic organization of lbp is shown in Figure 4A, with genes color-coded on the basis of their proposed functions summarized in Table 3. The nucleotide sequences were deposited in GenBank (MN396889). The lbp BGC contains six inconsecutive genes lbpA1A6, similar to lobA1A5 in lob from S. sp. SCSIO 01127. Differently, the LobA4 homologue is separated into two polyketide synthases (PKSs), LbpA4 and LbpA5, in lbp. The high similarity between the PKS modules in lbp and in lob enables us to propose that the assembly of the linear polyketide chain catalyzed by LbpA1–A6 utilizes six malonyl CoAs, six methylmalonyl-CoAs, and a 3-carbon glycerol unit (Figure 5) [11]. The lbp harbors four putative regulator genes (lbpR1–R4) (Figure 4 and Table 3) that are highly similar to lobR1, lobR3, lobR4, and lobR5 in lob, respectively. These four regulators are assumed to be involved in the regulation network of lobophorin CR4 biosynthesis, which seems to be less complex than lob but more complex than kij [7] and tca [8]. In contrast, five regulator genes lobR1–R5 are identified in lob; three regulator genes, kijA8, kijC5, and kijD12, are included in kij; tcaR1 and tcaR2 both encode regulators in tca. There is only one gene, lbpU2 in lbp, with no apparent homologue in lob (Figure 4 and Table 3). The other genes included in lbp are putatively associated with the biosynthesis of kijanose and l-digitoxose units by virtue of high similarities to corresponding counterparts in lob (Figure 4 and Table 3).
To demonstrate the validity of the putative lbp BGC, lbpC4 coding for ketosynthase-III-like protein, which incorporates a 3-carbon glycerol unit into the biosynthetic precursor LOB aglycon [11], was disrupted by using PCR-targeting methods. As expected, the production of lobophorin CR4 was completely blocked in S. olivaceus SCSIO T05/ΔrsdK2xmcPlbpC4 (S. olivaceus SCSIO T05RXL) (Figure 2, trace iv), demonstrating that the lbp BGC is indeed responsible for lobophorin biosynthesis. With high similarity to the lob BGC, the lbp BGC accounts for lobophorin CR4 without the attachment of kijanose to C17-OH, rather than lobophorins A and B in lob. Based on bioinformatics analysis, a series of enzymes are proposed to be involved in kijanose biosynthesis (Figure 5) [7]. Among them, the amino acid sequence of the putative FAD-dependent oxidoreductase LbpP2 is far shorter than its homologues LobP2 [11] and KijB3 [7]. KijB3 is proposed to oxidize the methyl group to a carboxylate group, essential for the generation of the kijanose moiety [7]. Multiple protein sequence alignments of LbpP2, LobP2, and KijB3 revealed that the conserved FAD binding domain is missing in LbpP2 (Figure S5). Thus, we speculate that LbpP2 is nonfunctional, failing to catalyze the carboxylation and hinder the generation of kijanose.
Given the high similarity of LbpG3 and LobG3, we envision that LbpG3 has a similar function as LobG3, a glycosyltransferase from S. sp. SCSIO 01127, tandemly attaching the first two l-digitoxose at C-9 in lobophorins [11]. LbpG2 has 99% similarity to LobG2, another glycosyltransferase from the same strain, which was established to transfer the terminal l-digitoxose [11]. Both LbpG2 and LbpG3 are likely to be involved in the transfers of three sugar units, sugars A, B, and C, in lobophorin CR4 (Figure 5), consistent with the metabolite profile of ΔlobG1 in S. sp. SCSIO 01127 [11].

3. Experimental Section

3.1. General Experimental Procedures

The plasmids and bacteria used are listed in Table S1. Streptomyces olivaceus SCSIO T05 and its mutants were incubated on modified ISP-4 medium [25] with 3% sea salt and fermented in modified RA medium [19]. All cultures for Streptomyces were incubated at 28 °C. Luria-Bertani (LB) medium was used for E. coli, with appropriate antibiotics added at a final concentration of 100 µg/mL of ampicillin (Amp), 50 µg/mL of kanamycin (Kan), 50 µg/mL of apramycin (Apr), 25 µg/mL of chloroamphenicol (Cml), and 50 µg/mL of trimethoprim (TMP).
A 1260 infinity system (Agilent, Santa Clara, CA, USA), which uses a Phenomenex Prodigy ODS (2) column (150 × 4.6 mm, 5 μm, USA), was used for HPLC-based analyses. Silica gel with the size of 100–200 mesh (Jiangpeng Silica gel development, Inc., Shandong, China) was used for column chromatography (CC). A Primaide 1110 solvent delivery module, which is equipped with a 1430 photodiode array detector (Hitachi, Tokyo, Japan) and uses a YMC-Pack ODS-A column (250 mm × 10 mm, 5 μm), was used for semi-preparative HPLC. A MaXis Q-TOF mass spectrometer (Bruker, Billerica, MA, USA) was used to acquire high-resolution mass spectral data. An MCP-500 polarimeter (Anton Paar, Graz, Austria) was used to record optical rotations. A Bruker Avance 500 was used to record NMR spectra. Carbon signals and the residual proton signals of DMSO-d6 were used for calibration (δC 39.52 and δH 2.50).

3.2. Genome Sequencing and Bioinformatic Analysis

Whole genome scanning and annotation of S. olivaceus SCSIO T05 were acquired by the single-molecule real-time (SMRT) sequencing technology (PacBio) at Shanghai Majorbio Bio-Pharm Technology Co., Ltd (Shanghai, China). AntiSMASH (AntiSMASH 5.0, available at http://antismash.secondarymetabolites.org/) was used to analyze and assess the potential BGCs. FramePlot (FramePlot 4.0 beta, available at http://nocardia.nih.go.jp/fp4/) was used to analyze ORFs whose functions were predicted based on an online BLAST program (http://blast.ncbi.nlm.nih.gov/).

3.3. Construction of a “Triple-Deletion” Mutant Strain

Gene lbpC4 from the lbp BGC was inactivated by the REDIRECT protocol [26]. All primers used in this study are listed in Table S2. LbpC4 was replaced by the apramycin resistance gene oriT/aac(3)IV fragment in the target cosmids 01-07D or 21-02E. The target mutant clones, S. olivaceus SCSIO T05RXL, were accomplished as previously described [19,23,24].

3.4. Fermentation and HPLC-based Analyses of S. olivaceus SCSIO T05 and Its Mutants

The Streptomyces used in this study were incubated in modified ISP-4 medium plates for 2–3 d. For fermentation, a portion of mycelium and spores was seeded into 50 mL of modified RA medium in a 250 mL flask and then shaken at 200 rpm and 28 °C for 8 d. The cultures were extracted with an equal volume of butanone. Organic phases were then dissolved in CH3OH (1 mL) after having been evaporated to dryness, and 40 µL of each relevant sample was injected for HPLC-based analysis. The UV detection was at 254 nm. Solvent A is composed of 85% ddH2O and 15% CH3CN, supplemented with 0.1% HOAc. Solvent B is composed of 85% CH3CN and 15% ddH2O, supplemented with 0.1% HOAc. Samples were analyzed via the following method: a linear gradient from 0% to 80% solvent B in 20 min, and then, from 80% to 100% solvent B for 1.5 min, finally eluted with 100% solvent B in 6.5 min. The flow rate was 1.0 mL/min.

3.5. Production, Isolation, and Structure Elucidation of Lobophorin CR4

The mycelium of S. olivaceus SCSIO T05RX were inoculated into 50 mL of modified-RA medium and then shaken at 200 rpm and 28 °C for 2 d, to gain the seed cultures. After that, the seed cultures were transferred into 150 mL of modified-RA medium and shaken at 200 rpm and 28 °C for 8 d. After the large-scale fermentation was accomplished, a total of 12 L of the growth culture was centrifuged at 4000 g for 10 min to separate the supernatant and mycelium and further extracted by butanone and acetone, respectively. The two organic phases were concentrated (via solvent removal under vacuum), and the residues were combined. The combined sample was subjected to normal phase silica gel CC eluted with CHCl3-CH3OH (100:0, 98:2, 96:4, 94:6, 92:8, 90:10, 85:15, 80:20, 70:30, 50:50, v/v, each solvent combination in 250 mL volume) to give ten fractions (AFr.1–AFr.10). Fractions A1-A3 were purified to afford the accumulation of compound 1 (98 mg), by preparative HPLC, eluting with 90% solvent B (A: H2O; B: CH3CN) over the course of 30 min. The flowrate was 2.5 mL/min and the UV detection was at 254 nm. The purified compound was subjected to MS, 1H, and 13C NMR spectra measurements and elucidated as a known intermediate 3 during lobophorins A and B biosynthesis [11], and we named it lobophorin CR4 (1).

4. Conclusions

In this study, we acquired the complete genome sequence of S. olivaceus SCSIO T05. The biosynthetically talented strain harbors 37 putative BGCs analyzed by antiSMASH. To explore the biosynthetic potential of this strain, metabolic engineering and genome mining were performed. The major anthracenes and indolosesquiterpenes biosynthetic pathways were blocked, and an orphan spirotetronate antibiotics BGC (lbp) was activated in S. olivaceus SCSIO T05, leading to the isolation and identification of one known compound, lobophorin CR4. We have identified the lbp BGC accounting for lobophorin biosynthesis by gene-disruption experiments and bioinformatics analysis. The production of lobophorin CR4 without the attachment of d-kijanose to C17-OH was on account that the nonfunctional FAD-dependent oxidoreductase LbpP2 failed to generate d-kijanose. This work highlights that metabolic engineering and genome mining are the effective ways to turn on putative orphan or silent BGCs to acquire new NPs for drugs discovery.

Supplementary Materials

The following are available online at https://www.mdpi.com/1660-3397/17/10/593/s1. This section includes HRESIMS, 1D NMR spectra for compound 1, construction of ΔlbpC4.

Author Contributions

C.Z. performed the experiments and wrote the draft manuscript. W.D. performed the isolation of compound 1. X.Q. helped to perform the sequence alignments. J.J. supervised the whole work and edited the manuscript. All authors read and approved the final manuscript.

Funding

This research was funded by the National Natural Science Foundation of China (81425022, U1706206, and U1501223), and Natural Science Foundation of Guangdong Province (2016A030312014).

Acknowledgments

We are grateful to Aijun Sun, Xiaohong Zheng, Yun Zhang, Xuan Ma, and Zhihui Xiao, in the analytical facility center of the SCSIO for recording MS and NMR data.

Conflicts of Interest

The authors declare no conflicts of interest.

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Figure 1. The complete genome of S. olivaceus SCSIO T05. The three circles (inner to outer) represent forward GC content, GC skew, and the distribution of putative biosynthetic gene clusters (BGCs) (represented by the bars) generated by antiSMASH 5.0. Clusters 18, 17, and 11 were described as rishirilides, xiamycins, and mycemycins BGCs, respectively. The putative lobophorin BGC with red color was referred to as cluster 37.
Figure 1. The complete genome of S. olivaceus SCSIO T05. The three circles (inner to outer) represent forward GC content, GC skew, and the distribution of putative biosynthetic gene clusters (BGCs) (represented by the bars) generated by antiSMASH 5.0. Clusters 18, 17, and 11 were described as rishirilides, xiamycins, and mycemycins BGCs, respectively. The putative lobophorin BGC with red color was referred to as cluster 37.
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Figure 2. HPLC-based analyses of fermentation broths: (i) S. olivaceus SCSIO T05; (ii) S. olivaceus SCSIO T05R; (iii) S. olivaceus SCSIO T05RX; and (iv) S. olivaceus SCSIO T05RXL. Compound 1 is lobophorin CR4. Compounds 26 were previously identified as rishirilide B, rishirilide C, lupinacidin A, galvaquinone B, and xiamycin A, respectively.
Figure 2. HPLC-based analyses of fermentation broths: (i) S. olivaceus SCSIO T05; (ii) S. olivaceus SCSIO T05R; (iii) S. olivaceus SCSIO T05RX; and (iv) S. olivaceus SCSIO T05RXL. Compound 1 is lobophorin CR4. Compounds 26 were previously identified as rishirilide B, rishirilide C, lupinacidin A, galvaquinone B, and xiamycin A, respectively.
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Figure 3. Structure of the isolated lobophorin CR4.
Figure 3. Structure of the isolated lobophorin CR4.
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Figure 4. Genetic organizations: (A) the lbp BGC from S. olivaceus SCSIO T05; (B) the lob BGC from S. sp. SCSIO 01127.
Figure 4. Genetic organizations: (A) the lbp BGC from S. olivaceus SCSIO T05; (B) the lob BGC from S. sp. SCSIO 01127.
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Figure 5. Proposed biosynthetic pathway of lobophorin CR4.
Figure 5. Proposed biosynthetic pathway of lobophorin CR4.
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Table 1. Genome features of S. olivaceus SCSIO T05.
Table 1. Genome features of S. olivaceus SCSIO T05.
FeatureValue
Genome size (bp)8,458,055
Average GC content (%)72.51
Protein-coding genes7700
Total size of Protein-coding genes (bp)7,543,173
rRNAs number18
tRNAs number65
Table 2. AntiSMASH-predicted BGCs for S. olivaceus SCSIO T05.
Table 2. AntiSMASH-predicted BGCs for S. olivaceus SCSIO T05.
BGCPositionType (Product)
FromTo
Cluster 1272589768Type I Polyketide synthase (T1 PKS)
Cluster 2234616284137Non-ribosomal peptide synthetase (NRPS) cluster
Cluster 3504553512728Bacteriocin or other unspecified ribosomally synthesized and post-translationally modified peptide product (RiPP) cluster (Bacteriocin)
Cluster 4525945544617Terpene
Cluster 5793277855894NRPS
Cluster 6901333979368T1 PKS
Cluster 79808911005613Lanthipeptide cluster (Lanthipeptide)
Cluster 811358861240760Other types of PKS cluster (Otherks)-NRPS
Cluster 912751641347740NRPS-Terpene
Cluster 1016517111694648NRPS-Nucleoside cluster (Nucleoside)
Cluster 1116950201734380Otherks
Cluster 1217516981796277NRPS
Cluster 1318400511851963Siderophore cluster (Siderophore)
Cluster 1419674511990613Lanthipeptide
Cluster 1520377722059400Terpene
Cluster 1620906802102023Bacteriocin
Cluster 1721388602187226T1PKS-NRPS
Cluster 1822306912317060NRPS-Type II PKS (T2 PKS)-Otherks
Cluster 1923307352352337Lanthipeptide
Cluster 2024439072456009Siderophore
Cluster 2129057482978302T2 PKS
Cluster 2230290683048760Terpene
Cluster 2330498063075321Beta-lactone containing protease inhibitor (Betalactone)
Cluster 2431827763235915NRPS
Cluster 2537644723822515NRPS
Cluster 2641314104159582Lanthipeptide
Cluster 2748812964901736Phenazine cluster (Phenazine)
Cluster 2856339795656500Lasso peptide cluster (Lassopeptide)
Cluster 2957169305727556Melanin cluster (Melanin)
Cluster 3066673856677783Ectoine cluster (Ectoine)
Cluster 3172009307253804NRPS
Cluster 3273288187368924Type III PKS (T3 PKS)
Cluster 3376148147636052Aminoglycoside/aminocyclitol cluster (Amglyccycl)
Cluster 3478828837906528Terpene
Cluster 3579596957980831Indole cluster (Indole)
Cluster 3682005608221618Terpene
Cluster 3782396558455702T1pks-Nrps-T3 PKS-Oligosaccharide cluster (Oligosaccharide)-Other
Table 3. Deduced function of open reading frames (ORFs) in the lbp BGC.
Table 3. Deduced function of open reading frames (ORFs) in the lbp BGC.
ORFSize aProposed FunctionID/SI bProtein Homologue and Origin
orf(-2)374macrolide glycosyltransferase100/100Orf(-2) (AGI99472.1); Streptomyces sp. SCSIO 01127
orf(-1)260FkbM family methyltransferase100/100Orf(-1) (AGI99473.1); Streptomyces sp. SCSIO 01127
lbpR1195TetR type regulatory protein100/100lobR1 (AGI99474.1); Streptomyces sp. SCSIO 01127
lbpT1497efflux permease100/100lobT1 (AGI99475.1); Streptomyces sp. SCSIO 01127
lbpP1392p450 monooxygenase100/100lobP1 (AGI99476.1); Streptomyces sp. SCSIO 01127
lbpU1326aldo/keto reductase100/100lobU1 (AGI99477.1); Streptomyces sp. SCSIO 01127
lbpS1271sugar-O-methyltransferase99/100lobS1 (AGI99478.1); Streptomyces sp. SCSIO 01127
lbpS2384sugar 4-aminotransferase100/100lobS2 (AGI99479.1); Streptomyces sp. SCSIO 01127
lbpS3201SAM-dependent methyltransferase97/98lobS3 (AGI99480.1); Streptomyces sp. SCSIO 01127
lbpU2197hypothetical protein100/100hypothetical protein (KMB22099.1); Klebsiella pneumoniae
lbpG1391glycosyltransferase100/100lobG1 (AGI99481.1); Streptomyces sp. SCSIO 01127
lbpA13936PKS
(KS-AT-DH-ER-KR-ACP-KS-AT-DH-KR-ACP)
100/100lobA1 (AGI99482.1); Streptomyces sp. SCSIO 01127
lbpS4483sugar 2,3-dehydratase100/100lobS4 (AGI99483.1); Streptomyces sp. SCSIO 01127
lbpB253thioesterase100/100lobB (AGI99484.1); Streptomyces sp. SCSIO 01127
lbpP2313FAD-dependent oxidoreductase100/100part of lobP2 (AGI99485.1); Streptomyces sp. SCSIO 01127
lbpG2416glycosyltransferase99/100lobG2 (AGI99486.1); Streptomyces sp. SCSIO 01127
lbpG3476glycosyltransferase99/100lobG3 (AGI99487.1); Streptomyces sp. SCSIO 01127
lbpC1680hydrolase superfamily dihydrolipo-amide acyltransferase-like protein99/99lobC1 (AGI99489.1); Streptomyces sp. SCSIO 01127
lbpC275ACP99/100lobC2 (AGI99490.1); Streptomyces sp. SCSIO 01127
lbpC3621FkbH-like protein99/100lobC3 (AGI99491.1); Streptomyces sp. SCSIO 01127
lbpC4342ketoacyl acyl carrier protein synthase III100/100lobC4 (AGI99492.1); Streptomyces sp. SCSIO 01127
lbpP3492FAD-dependent oxidoreductase100/100lobP3 (AGI99493.1); Streptomyces sp. SCSIO 01127
lbpA21573PKS
(KS-AT-KR-ACP)
99/100lobA2 (AGI99494.1); Streptomyces sp. SCSIO 01127
lbpA31798PKS
(KS-AT-DH-KR-ACP)
99/99lobA3 (AGI99495.1); Streptomyces sp. SCSIO 01127
lbpA44376PKS
(KR-ACP-KS-AT-DH-KR-ACP-KS-AT-DH-KR-ACP)
100/100part of lobA4 (AGI99496.1); Streptomyces sp. SCSIO 01127
lbpA52881PKS
(KS-AT-DH-KR-ACP-KS-AT-DH)
99/98part of lobA4 (AGI99496.1); Streptomyces sp. SCSIO 01127
lbpA66362PKS
(KS-AT-ACP-KS-AT-DH-KR-ACP-KS-AT-DH-KR-ACP-KS-AT-DH-KR-ACP)
99/99lobA5 (AGI99497.1); Streptomyces sp. SCSIO 01127
lbpU3151unknown100/100lobU2 (AGI99498.1); Streptomyces sp. SCSIO 01127
lbpS5414sugar 3-C-methyl transferase100/100lobS5 (AGI99499.1); Streptomyces sp. SCSIO 01127
lbpS6373sugar 3-aminotransferase100/100lobS6 (AGI99500.1); Streptomyces sp. SCSIO 01127
lbpS7439acyl-CoA dehydrogenase100/100lobS7 (AGI99501.1); Streptomyces sp. SCSIO 01127
lbpS8341sugar 4,6-dehydratase100/100lobS8 (AGI99502.1); Streptomyces sp. SCSIO 01127
lbpS9298sugar nucleotidyltransferase99/100lobS9 (AGI99503.1); Streptomyces sp. SCSIO 01127
lbpS10332sugar 3-ketoreductase100/100lobS10 (AGI99504.1); Streptomyces sp. SCSIO 01127
lbpS11202sugar 5-epimerase99/100lobS11 (AGI99505.1); Streptomyces sp. SCSIO 01127
lbpR2274TetR type regulatory protein99/100lobR3 (AGI99506.1); Streptomyces sp. SCSIO 01127
lbpT2211forkhead-associated protein99/100lobT2 (AGI99507.1); Streptomyces sp. SCSIO 01127
lbpR3298putative regulatory protein99/100lobR4 (AGI99508.1); Streptomyces sp. SCSIO 01127
lbpR4309LysR family transcriptional regulator99/100lobR5 (AGI99509.1); Streptomyces sp. SCSIO 01127
orf1183acetyltransferase100/100Orf1 (AGI99510.1); Streptomyces sp. SCSIO 01127
a Amino acids. b Identity/similarity.
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