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1.
Dumitrita Iftime Martin Jasyk Andreas Kulik Prof. Dr. Johannes F. Imhoff Dr. Evi Stegmann Prof. Dr. Wolfgang Wohlleben Prof. Dr. Roderich D. Süssmuth Dr. Tilmann Weber 《Chembiochem : a European journal of chemical biology》2015,16(18):2615-2623
Lanthipeptides are ribosomally synthesized and post‐translationally modified microbial secondary metabolites. Here, we report the identification and isolation of streptocollin from Streptomyces collinus Tü 365, a new member of class IV lanthipeptides. Insertion of the constitutive ermE* promoter upstream of the lanthipeptide synthetase gene stcL resulted in peptide production. The streptocollin gene cluster was heterologously expressed in S. coelicolor M1146 and M1152 with 3.5‐ and 5.5‐fold increased yields, respectively. The structure and ring topology of streptocollin were determined by high resolution MS/MS analysis. Streptocollin contains four macrocyclic rings, with one lanthionine and three methyllanthionine residues. To the best of our knowledge, this is the first report on the isolation of a class IV lanthipeptide in preparative amounts, and on the successful heterologous expression of a class IV lanthipeptide gene cluster. 相似文献
2.
Salman Ahmed Dr. Arryn Craney Dr. Sheila M. Pimentel‐Elardo Prof. Justin R. Nodwell 《Chembiochem : a European journal of chemical biology》2013,14(1):83-91
The secondary metabolites produced by bacterial species serve many clinically useful purposes, and Streptomyces have been an abundant source of such compounds. However, a poor understanding of their regulatory cascades leads to an inability to isolate all of the secondary metabolites this genus is capable of producing. This study focuses on comparing synthetic small molecules that were found to alter the production of secondary metabolites in Streptomyces coelicolor. A survey of these molecules suggests that each has a distinct mechanism of action, and hence, could be used as a unique probe of secondary metabolism. A comparative analysis of two of these molecules, ARC2 and ARC6, confirmed that they modulate secondary metabolites in different ways. In a separate study, ARC2 was shown to give rise to a different phenotype through the inhibition of a target in fatty acid biosynthesis. The results of this study suggest that ARC6 does not have the same target, although it might target the same metabolic system. Furthermore, the results demonstrate that ARC2 and ARC6 act through distinct mechanisms and further suggest that chemical probes can be important tools in enhancing our understanding of secondary metabolism and the streptomycete life cycle. 相似文献
3.
Völler GH Krawczyk JM Pesic A Krawczyk B Nachtigall J Süssmuth RD 《Chembiochem : a European journal of chemical biology》2012,13(8):1174-1183
Lantibiotics are a large group of ribosomally synthesized peptides post-translationally modified to incorporate the amino acid lanthionine. They are classified, according to their biosynthetic pathway and bioactivity, into three major subtypes. Of Actinomycetes type III lantibiotics, only four peptides (SapB, SapT, LabA1, and LabA2) have been described and structurally characterized, although homologous gene clusters are abundant in other Actinomycetes. All these gene clusters share a similar architecture with a characteristic Ser/Ser/Cys motif in precursor peptides, which has previously been suggested to act as a precursor for lanthionine (SapB) and labionin (LabA2) rings. Mass spectrometry screening led to the discovery and characterization of three new representatives of type III lantibiotics: Avermipeptin (Avi), Erythreapeptin (Ery), and Griseopeptin (Gri) from Streptomyces avermitilis DSM 46492, Saccharopolyspora erythraea NRRL 2338, and Streptomyces griseus DSM 40236, respectively. Apart from the assignment of these peptides to their corresponding gene clusters, additional investigations on Avi, Ery and Gri peptides indicate stepwise leader processing by putative aminopeptidase-like protease(s), thus yielding mixtures of differently N-terminal-processed lantibiotic peptides. Similar peptide processing was observed for a heterologously expressed eryth biosynthetic gene cluster expressed in a Streptomyces host system. Remarkably, all isolates of the new type III lantibiotics contain both the amino acids lanthionine and labionin, thus implying dual-mode cyclase activity of the processing lyase-kinase-cyclase enzymes. These findings have implications for the structures and maturation of other type III lantibiotics from Actinomycetes. 相似文献
4.
Streptomyces violaceoruber grown in co-culture with Streptomyces aburaviensis produces an about 17-fold higher volume of droplets on its aerial mycelium than in single-culture. Physical separation of the Streptomyces strains by either a plastic barrier or by a dialysis membrane, which allowed communication only by the exchange of volatile compounds or diffusible compounds in the medium, respectively, still resulted in enhanced droplet formation. The application of molecular sieves to bioassays resulted in the attenuation of the droplet-inducing effect of S. aburaviensis indicating the absorption of the compound. 1H-NMR analysis of molecular-sieve extracts and the selective indophenol-blue reaction revealed that the volatile droplet-inducing compound is ammonia. The external supply of ammonia in biologically relevant concentrations of ≥8 mM enhanced droplet formation in S. violaceoruber in a similar way to S. aburaviensis. Ammonia appears to trigger droplet production in many Streptomyces strains because four out of six Streptomyces strains exposed to ammonia exhibited induced droplet production. 相似文献
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6.
Identification of Fluorinases from Streptomyces sp MA37, Norcardia brasiliensis,and Actinoplanes sp N902‐109 by Genome Mining
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Dr. Hai Deng Dr. Long Ma Nouchali Bandaranayaka Zhiwei Qin Greg Mann Dr. Kwaku Kyeremeh Dr. Yi Yu Dr. Thomas Shepherd Prof. James H. Naismith Prof. David O'Hagan 《Chembiochem : a European journal of chemical biology》2014,15(3):364-368
The fluorinase is an enzyme that catalyses the combination of S‐adenosyl‐L ‐methionine (SAM) and a fluoride ion to generate 5′‐fluorodeoxy adenosine (FDA) and L ‐methionine through a nucleophilic substitution reaction with a fluoride ion as the nucleophile. It is the only native fluorination enzyme that has been characterised. The fluorinase was isolated in 2002 from Streptomyces cattleya, and, to date, this has been the only source of the fluorinase enzyme. Herein, we report three new fluorinase isolates that have been identified by genome mining. The novel fluorinases from Streptomyces sp. MA37, Nocardia brasiliensis, and an Actinoplanes sp. have high homology (80–87 % identity) to the original S. cattleya enzyme. They all possess a characteristic 21‐residue loop. The three newly identified genes were overexpressed in E. coli and shown to be fluorination enzymes. An X‐ray crystallographic study of the Streptomyces sp. MA37 enzyme demonstrated that it is almost identical in structure to the original fluorinase. Culturing of the Streptomyces sp. MA37 strain demonstrated that it not only also elaborates the fluorometabolites, fluoroacetate and 4‐fluorothreonine, similar to S. cattleya, but this strain also produces a range of unidentified fluorometabolites. These are the first new fluorinases to be reported since the first isolate, over a decade ago, and their identification extends the range of fluorination genes available for fluorination biotechnology. 相似文献
7.
Separation of the two reactions, oxidation and isomerization, catalyzed by Streptomyces cholesterol oxidase 总被引:1,自引:0,他引:1
Yamashita M; Toyama M; Ono H; Fujii I; Hirayama N; Murooka Y 《Protein engineering, design & selection : PEDS》1998,11(11):1075-1081
Site-directed mutagenesis was used to identify key amino acid residues of
the cholesterol oxidase from Streptomyces sp., which catalyzes the
oxidation of cholesterol and the isomerization of 5-cholesten-3-one. Eight
mutant enzymes were constructed and the following amino acid substitutions
were identified: N318A, N318H, E356A, E356D, H441A, H441N, N480A and N480Q.
Mutants N318A and N318H retained both oxidation and isomerization
activities. The mutant E356D retained oxidation but not isomerization
activity. On the other hand, mutants N480A and N480Q showed no oxidation
activity but retained their isomerization activities. The two catalytic
reactions, oxidation and isomerization, in cholesterol oxidase were thus
successfully separated. When the H441A or H441N mutation was introduced,
both the oxidase and isomerase activities were completely lost. The H441,
E356 and N480 residues thus appear to participate in the catalysis of
cholesterol oxidase, whereas N318 does not. An analysis of the products of
these mutant enzymes suggested that the previously proposed 6-hydroxylation
reaction by cholesterol oxidase is actually autooxidation from
5-cholesten-3-one. Kinetic studies of the purified wild-type and mutant
enzymes showed that the k(cat)/Km values for oxidation in E356D and for
isomerization in N480A increased six- and threefold, respectively, over
those in the wild-type. These mutational effects and the reaction
mechanisms are discussed in terms of the three-dimensional structure of the
enzyme constructed on the basis of homology modeling.
相似文献
8.
Stephan Rehm Sigeng Han Ismail Hassani Alma Sokocevic Hendrik R. A. Jonker Dr. Joachim W. Engels Prof. Dr. Harald Schwalbe Prof. Dr. 《Chembiochem : a European journal of chemical biology》2009,10(1):119-127
The protein parvulustat (Z‐2685) from Streptomyces parvulus comprises 78 amino acids and functions as a highly efficient α‐amylase inhibitor. Parvulustat shares 29.6 % overall amino acid sequence identity to the well‐known α‐amylase inhibitor tendamistat. Among the conserved residues are the two disulfide bridges (C9–C25, C43–C70) and the active‐site motif (W16, R17, Y18). Here, we report the high‐resolution NMR structure of parvulustat based on NOEs, J couplings, chemical shifts and hydrogen‐exchange data. In addition, we studied the dynamical properties of parvulustat by heteronuclear relaxation measurements. We compare the structure of parvulustat with the structure of tendamistat in terms of secondary structure elements, charges and hydrophobicity. The overall structural composition is very similar, but there are distinct differences including the active‐site region. These structural and dynamical differences indicate that for parvulustat an induced‐fit mechanism for binding to α‐amylase might take place, since the structure of tendamistat does not change upon binding to α‐amylase. 相似文献
9.
L Addour D Belhocine N Boudries Y Comeau A Pauss N Mameri 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1999,74(11):1089-1095
The ability of Streptomyces rimosus biomass to bind zinc ions in batch mode was shown recently. The aim of this study was to determine the zinc uptake capacity by Streptomyces rimosus biomass in continuous mode. Bacterial biomass was able to bind more Zn(II) after pretreatment with sodium hydroxide (1 mol dm−3) than without treatment. The maximum adsorption capacity and the adsorption capacity at the saturation point calculated by means of both the exchange zone model and the Thomas model were practically identical of about 2.9 mgZn(II) g−1biomass. This result was lower than the batch adsorption capacity of Streptomyces rimosus, indicating that the packed‐bed is not the most appropriate process to exploit the bacterial biomass adsorption capacity. The effect of zinc concentration in the range of 10 to 200 mgZn(II) dm−3 on the biosorption capacity of the packed‐bed was not significant. Biomass regeneration with 0.1 mol dm−3 HCl gave a 90% recovery of the adsorbed Zn(II). © 1999 Society of Chemical Industry 相似文献
10.
Won-Bok Chae Young-Bum Kim Sung-Won Choi Hyang-Bok Lee Eun-Ki Kim 《Korean Journal of Chemical Engineering》2009,26(2):438-443
To be an effective microbial biocide, Streptomyces kasugaensis should be converted into spore during cultivation process for successful long-term storage. By statistical design methods,
culture conditions including medium components and operating parameters were optimized and more than 100 times increase in
spore yield was achieved. Addition of spent culture fluid (100 ppm), EDTA (30 ppm), mycophenolic acid (32 ppm) with combination
of pH up-shock (5.5 to 8.5) increased total viable cell and spore conversion rate, resulting in 1.6×107 (spore/mL) in 5 days of culture in a fermenter. This result provides a practical method for obtaining high spore number for
commercial production of Streptomyces kasugaensis as a microbial pesticide. 相似文献
11.
Photometric Characterization of the Reductive Amination Scope of the Imine Reductases from Streptomyces tsukubaensis and Streptomyces ipomoeae
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Philipp Matzel Lukas Krautschick Prof. Matthias Höhne 《Chembiochem : a European journal of chemical biology》2017,18(20):2022-2027
Imine reductases (IREDs) have emerged as promising enzymes for the asymmetric synthesis of secondary and tertiary amines starting from carbonyl substrates. Screening the substrate specificity of the reductive amination reaction is usually performed by time-consuming GC analytics. We found two highly active IREDs in our enzyme collection, IR-20 from Streptomyces tsukubaensis and IR-Sip from Streptomyces ipomoeae, that allowed a comprehensive substrate screening with a photometric NADPH assay. We screened 39 carbonyl substrates combined with 17 amines as nucleophiles. Activity data from 663 combinations provided a clear picture about substrate specificity and capabilities in the reductive amination of these enzymes. Besides aliphatic aldehydes, the IREDs accepted various cyclic (C4–C8) and acyclic ketones, preferentially with methylamine. IR-Sip also accepted a range of primary and secondary amines as nucleophiles. In biocatalytic reactions, IR-Sip converted (R)-3-methylcyclohexanone with dimethylamine or pyrrolidine with high diastereoselectivity (>94–96 % de). The nucleophile acceptor spectrum depended on the carbonyl substrate employed. The conversion of well-accepted substrates could also be detected if crude lysates were employed as the enzyme source. 相似文献
12.
Dr. Marta Wojnowska Dr. Xuan Feng Yawen Chen Dr. Hai Deng Prof. Dr. David O'Hagan 《Chembiochem : a European journal of chemical biology》2023,24(5):e202200684
The gene cluster in Streptomyces calvus associated with the biosynthesis of the fluoro- and sulfamyl-metabolite nucleocidin was interrogated by systematic gene knockouts. Out of the 26 gene deletions, most did not affect fluorometabolite production, nine abolished sulfamylation but not fluorination, and three precluded fluorination, but had no effect on sulfamylation. In addition to nucI, nucG, nucJ, nucK, nucL, nucN, nucO, nucQ and nucP, we identified two genes (nucW, nucA), belonging to a phosphoadenosine phosphosulfate (PAPS) gene cluster, as required for sulfamyl assembly. Three genes (orf(−3), orf2 and orf3) were found to be essential for fluorination, although the activities of their protein products are unknown. These genes as well as nucK, nucN, nucO and nucPNP, whose knockouts produced results differing from those described in a recent report, were also deleted in Streptomyces virens – with confirmatory outcomes. This genetic profile should inform biochemistry aimed at uncovering the enzymology behind nucleocidin biosynthesis. 相似文献
13.
Cone MC Yin X Grochowski LL Parker MR Zabriskie TM 《Chembiochem : a European journal of chemical biology》2003,4(9):821-828
Blasticidin S is a potent antifungal and cytotoxic peptidyl nucleoside antibiotic from Streptomyces griseochromogenes. The mixed biosynthesis of the compound is evident from the three distinct structural components: a cytosine base, an amino deoxyglucuronic acid, and N-methyl beta-arginine. The blasticidin S biosynthesis gene cluster was cloned from S. griseochromogenes and the pathway heterologously expressed in S. lividans from a cosmid harboring a 36.7-kb fragment of S. griseochromogenes DNA. The complete DNA sequence of this insert has now been determined and evidence suggests a contiguous 20-kb section defines the blasticidin S biosynthesis cluster. The predicted functions of several open reading frames are consistent with the expected biochemistry and include an arginine 2,3-aminomutase, a cytosylglucuronic acid synthase, and a guanidino N-methyltransferase. Insight into other steps in the assembly of blasticidin S was evident from sequence homology with proteins of known function and heterologous expression of fragments of the cluster. Additionally, the gene that directs the production of free cytosine, blsM, was subcloned and expressed in Escherichia coli. Characterization of BlsM revealed that cytidine monophosphate serves as the precursor to cytosine. 相似文献
14.
Dr. María Rodríguez‐Mata Annika Frank Elizabeth Wells Dr. Friedemann Leipold Prof. Nicholas J. Turner Sam Hart Dr. Johan P. Turkenburg Dr. Gideon Grogan 《Chembiochem : a European journal of chemical biology》2013,14(11):1372-1379
NADPH‐dependent oxidoreductase Q1EQE0 from Streptomyces kanamyceticus catalyzes the asymmetric reduction of the prochiral monocyclic imine 2‐methyl‐1‐pyrroline to the chiral amine (R)‐2‐methylpyrrolidine with >99 % ee, and is thus of interest as a potential biocatalyst for the production of optically active amines. The structures of Q1EQE0 in native form, and in complex with the nicotinamide cofactor NADPH have been solved and refined to a resolution of 2.7 Å. Q1EQE0 functions as a dimer in which the monomer consists of an N‐terminal Rossman‐fold motif attached to a helical C‐terminal domain through a helix of 28 amino acids. The dimer is formed through reciprocal domain sharing in which the C‐terminal domains are swapped, with a substrate‐binding cleft formed between the N‐terminal subunit of monomer A and the C‐terminal subunit of monomer B. The structure is related to those of known β‐hydroxyacid dehydrogenases, except that the essential lysine, which serves as an acid/base in the (de)protonation of the nascent alcohol in those enzymes, is replaced by an aspartate residue, Asp187 in Q1EQE0. Mutation of Asp187 to either asparagine or alanine resulted in an inactive enzyme. 相似文献
15.
16.
Yong Wang Ying-ping Zhuang Ping Wang Ju Chu Si-liang Zhang 《Korean Journal of Chemical Engineering》2010,27(3):910-914
Effects of different ammonium sulfate concentrations on meilingmycin biosynthesis were studied in this research. The results
show that a lower concentration of ammonium ions stimulates the biosynthesis of meilingmycin, while a concentration higher
than 5 mmol/L inhibits the mycelial growth and the biosynthesis of the products. However, increased sugar consumption rate
with the elevated concentration of ammonium sulfate was observed during the fermentation process. On this basis, six enzymes,
which are responsible for the meilingmycin biosynthesis and the glucose metabolism, were measured and analyzed during the
bioprocess. The results suggest that glucose-6-phosphate dehydrogenase, citrate synthase, succinate dehydrogenase and fatty
acid synthase are stimulated by higher concentration of ammonium ions, while valine dehydrogenase and methylmalonyl-CoA carboxyltransferase
are inhibited. From the results it follows that the precursor supply was restricted with the higher concentration of ammonium
ions, which results in the lower production of meilingmycin. Thus, the strategy of maintaining a low level of FAS activity
is a critical factor for high yield of meilingmycin. 相似文献
17.
葡萄糖、磷酸盐对天蓝色链霉菌生长、代谢及蓝色素生成的影响 总被引:1,自引:0,他引:1
在天蓝色链霉菌分批发酵中,葡萄糖浓度的提高(4.76-16.8g/L)促进了菌体的生长;葡萄糖浓度的进一步提高(16.8-42.6g/L),菌体生长不变;再从42.6g/L增加到55.3g/L,菌体生长受到抑制。与之相对应,在这3个不同葡萄糖浓度范围内,色素产量随葡萄糖浓度增加而增加、缓慢下降及大幅度下降。磷酸盐浓度的提高(0.93-18.5mmol/L)促进了菌体生长,更高磷酸盐浓度对菌体的生长没有明显影响。除了低磷酸盐浓度(0.93mmol/L)外,磷酸盐浓度对葡萄糖的利用没有明显影响。初始磷酸盐浓度对色素生成影响很大,最佳浓度为9.56mmol/L。 相似文献
18.
19.
Radia Yous Faroudja Mohellebi Hakima Cherifi Abdeltif Amrane 《Korean Journal of Chemical Engineering》2018,35(4):890-899
The aim of this study is the simultaneous biosorption of Cd+2 and Ni+2 on a dead biomass, Streptomyces rimosus pretreated with NaOH (0,1 M). Kinetic tests were carried out for the binary mixture (cadmium-nickel) during 6 hours contact time to ensure that balance was reached. The amounts adsorbed at equilibrium were 22.8 mg Ni2+/g and 9.86 mg Cd2+/g biomass, respectively. The biosorption depends mainly by some parameters, such as the pH, the initial concentration of metal and the initial concentration of biomass. The isotherm of adsorption according to two models, Langmuir and Freundlich, was carried out in our study. The results of the kinetics of adsorption show that the experimental values are well represented by the kinetic model of pseudo-second order. This enables us to determine the behavior of these adsorbents with respect to a real industrial effluent. 相似文献
20.
Effect of Stereochemistry of Avermectin‐Like 6,6‐Spiroketals on Biological Activities and Endogenous Biotransformations in Streptomyces avermectinius
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Dr. Peng Sun Qunfei Zhao Hua Zhang Dr. Jiequn Wu Prof. Dr. Wen Liu 《Chembiochem : a European journal of chemical biology》2014,15(5):660-664
Natural avermectins (AVEs) share a 6,6‐spiroketal moiety with an exclusive R configuration at the C21 spirocyclic junction. Herein, we report the characterization of nine AVE‐like spiroketals of two types (C21 S and R) in a mutant strain that lacks spirocyclase activity. Comparative analysis of their structures facilitated evaluation of the effect of stereochemistry on endogenous biotransformations and biological activities of the spiroketals. 相似文献