Active site diversification of P450cam with indole generates catalysts for benzylic oxidation reactions

• Paul P. Kelly,
• Anja Eichler,
• Susanne Herter,
• David C. Kranz,
• Nicholas J. Turner and
• Sabine L. Flitsch

Beilstein J. Org. Chem. 2015, 11, 1713–1720, doi:10.3762/bjoc.11.186

• Escherichia coli (E. coli), variants of the fusion enzyme catalysed the efficient, highly selective hydroxylation of ionones without the need to supply expensive nicotinamide cofactors [20]. Given the previously demonstrated affinity of P450cam for hydrophobic substrates, we were interested to see if P450cam

SmI₂-mediated dimerization of indolylbutenones and synthesis of the myxobacterial natural product indiacen B

• Nils Marsch,
• Peter G. Jones and
• Thomas Lindel

Beilstein J. Org. Chem. 2015, 11, 1700–1706, doi:10.3762/bjoc.11.184

• natural product via X-ray analysis. Indiacen B (2) was tested against the Gram-positive bacteria Nocardioides simplex (1.7 µg/mL), Mycobacterium diernhoferi (no inhibition), and Mycobacterium sp. (8.3 µg/mL), and against the Gram-negative bacteria Escherichia coli TOL C (8.3 µg/mL), Chromobacterium

Pyridinoacridine alkaloids of marine origin: NMR and MS spectral data, synthesis, biosynthesis and biological activity

• Louis P. Sandjo,
• Victor Kuete and
• Maique W. Biavatti

Beilstein J. Org. Chem. 2015, 11, 1667–1699, doi:10.3762/bjoc.11.183

• of Trichophyton mentagrophytes (MIC 6.2 µg/mL) and Epidermophyton floccosum (MIC 1.6 µg/mL) [87]. Though no activity was observed against the gram negative bacteria Escherichia coli and Pseudomonas aeruginosa, meridine (56) significantly inhibited the growth of the gram positive bacteria Bacillus

• negative Escherichia coli and the gram positive Micrococcus luteus bacteria [56]. Interestingly, the 9H-quinolino[4,3,2-de][1,10]phenanthrolin-9-one core corresponding to the ascididemin (42) structure once again has proved to be a suitable antibacterial pharmacophore (Figure 17) [56]. The decrease in the

N-Alkyl derivatives of diosgenyl 2-amino-2-deoxy-β-D-glucopyranoside; synthesis and antimicrobial activity

• Agata Walczewska,
• Daria Grzywacz,
• Dorota Bednarczyk,
• Małgorzata Dawgul,
• Andrzej Nowacki,
• Wojciech Kamysz,
• Beata Liberek and
• Henryk Myszka

Beilstein J. Org. Chem. 2015, 11, 869–874, doi:10.3762/bjoc.11.97

• inhibitory activity against the Gram-negative bacteria, such as Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Proteus vulgaris and Pseudomonas aeruginosa. In contrast, almost all the tested N-alkyl saponins were found to inhibit the growth of the Gram-positive bacteria (Table 2). Among the

Mechanical stability of bivalent transition metal complexes analyzed by single-molecule force spectroscopy

• Manuel Gensler,
• Christian Eidamshaus,
• Maurice Taszarek,
• Hans-Ulrich Reissig and
• Jürgen P. Rabe

Beilstein J. Org. Chem. 2015, 11, 817–827, doi:10.3762/bjoc.11.91

• rb [6]. In natural environments, hydrodynamic effects may cause forces competing with biomolecular interactions, such as the leukocyte adhesion to endothelial cells [7] or the Escherichia coli adhesion to uroepithelium cells [8]. The latter has been well analyzed by single-molecule force spectroscopy

• Wollschläger et al. successfully detected a different binding of DNA to the corresponding domain in the transcription factor PhoB from Escherichia coli for the wild-type and slightly modified mutants [23]. Utilizing the sequential unzipping of transmembrane proteins, a full mechanical mapping was possible for

Synthesis of antibacterial 1,3-diyne-linked peptoids from an Ugi-4CR/Glaser coupling approach

• Martin C. N. Brauer,
• Ricardo A. W. Neves Filho,
• Bernhard Westermann,
• Ramona Heinke and
• Ludger A. Wessjohann

Beilstein J. Org. Chem. 2015, 11, 25–30, doi:10.3762/bjoc.11.4

• another study Chen and co-workers found a GLP-1R antagonist only because of an unexpected dimerization [5]; and a dimer of S-adenosylmethionine is up to 13-fold more active than the monomer for promoting the binding of Escherichia coli methionine repressor to its operator DNA [6]. Peptoids are compounds

Synthesis of the pentasaccharide repeating unit of the O-antigen of E. coli O117:K98:H4

• Pintu Kumar Mandal

Beilstein J. Org. Chem. 2014, 10, 2724–2728, doi:10.3762/bjoc.10.287

• coli; glycosylation; lipopolysaccharide; O-antigen; pentasaccharide; Introduction Escherichia coli becomes an important human pathogen in recent years owing to the emergence of new pathogenic strains [1]. Several diseases, such as meningitis and sepsis [2], diarrhoeal outbreaks [3] and urinary tract

• infections [4] are associated with pathogenic Escherichia coli (E. coli) strains. E. coli strains have been found to produce the Shiga toxin (Stx), heat-labile (LT) or heat-stable (ST) enterotoxins, cytotoxic necrotizing factors (CNF1 and CNF2) and hemolysins (α-Hly and E-Hly) [5][6] and are responsible for

• been synthesized using a combination of sequential glycosylations and [3 + 2] block synthetic strategy from the suitably protected monosaccharide intermediates. Thioglycosides and glycosyl trichloroacetimidate derivatives have been used as glycosyl donors in the glycosylations. Keywords: Escherichia

Encapsulation of biocides by cyclodextrins: toward synergistic effects against pathogens

• Véronique Nardello-Rataj and
• Loïc Leclercq

Beilstein J. Org. Chem. 2014, 10, 2603–2622, doi:10.3762/bjoc.10.273

• -hydroxybenzoate, benzyl alcohol, 2-phenoxyethanol) [45]. The authors established a clear relationship between the binding constants and the antimicrobial activity of the preservatives on various strains: Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli and C. albicans. Indeed, highly water-soluble

Gold(I)-catalysed synthesis of a furan analogue of thiamine pyrophosphate

• Amjid Iqbal,
• El-Habib Sahraoui and
• Finian J. Leeper

Beilstein J. Org. Chem. 2014, 10, 2580–2585, doi:10.3762/bjoc.10.270

• in Escherichia coli has been used in such studies but, in order to simplify the purification, in this study the gene was cloned into a pET28a vector, to give the enzyme an N-terminal His6-tag. This form of the protein was overexpressed in high yield in E. coli, and was easily purified on a Ni2+-NTA

Synthesis and biological evaluation of novel N-α-haloacylated homoserine lactones as quorum sensing modulators

• Michail Syrpas,
• Ewout Ruysbergh,
• Christian V. Stevens,
• Norbert De Kimpe and
• Sven Mangelinckx

Beilstein J. Org. Chem. 2014, 10, 2539–2549, doi:10.3762/bjoc.10.265

• . Furthermore, the biological QS activity of the synthetic AHL analogues compared to the natural AHLs was evaluated. Halogenated analogues demonstrated a reduced activity in the Escherichia coli JB523 bioassay, with the α-iodo lactones being the less active ones and the α-chloro AHLs the most potent QS agonists

• chlorinated AHL analogues 11a–f via reaction with S-homoserine lactone hydrobromide (1) and triethylamine (Scheme 3). Biological evaluation The above mentioned natural AHLs 3 and their halogenated analogues 6, 8 and 11 were first tested for their ability to induce fluorescence in the Escherichia coli JB523

• biosensor (Table 1). Escherichia coli JB523 is a highly sensitive reporter strain that contains plasmid pJBA130 derived from the LuxR-PluxI quorum sensing operon of Vibrio fischeri expressing the production of stable green fluorescent protein (GFP) in response to exogenous AHLs [31]. In addition, the

Autonomous assembly of synthetic oligonucleotides built from an expanded DNA alphabet. Total synthesis of a gene encoding kanamycin resistance

• Kristen K. Merritt,
• Kevin M. Bradley,
• Daniel Hutter,
• Mariko F. Matsuura,
• Diane J. Rowold and
• Steven A. Benner

Beilstein J. Org. Chem. 2014, 10, 2348–2360, doi:10.3762/bjoc.10.245

• overlapped assembly were then filled in using DNA polymerases, and the nicks were sealed by ligase. The S:B pairs in the ligated construct were then converted to T:A pairs during PCR amplification. When cloned into a plasmid, the product was shown to make Escherichia coli resistant to kanamycin. A parallel

Pyrrolidine nucleotide analogs with a tunable conformation

• Lenka Poštová Slavětínská,
• Dominik Rejman and
• Radek Pohl

Beilstein J. Org. Chem. 2014, 10, 1967–1980, doi:10.3762/bjoc.10.205

• -oxopurine phosphoribosyltransferases from Escherichia coli [6]. These biologically active analogs contain a five-membered pyrrolidine ring, whose conformation has not been explored so far. It is known that the conformation of a five-membered ribose or deoxyribose ring plays an important role in the

Application of cyclic phosphonamide reagents in the total synthesis of natural products and biologically active molecules

• Thilo Focken and
• Stephen Hanessian

Beilstein J. Org. Chem. 2014, 10, 1848–1877, doi:10.3762/bjoc.10.195

• carbapenems, which are powerful antibiotics with a broad spectrum of activity against Gram-positive and Gram-negative bacteria and are often used as antibiotics for many hard-to-treat bacterial infections, such as Escherichia coli and Klebsiella pneumoniae [88][89]. Resistance of bacterial strains to

Sacrolide A, a new antimicrobial and cytotoxic oxylipin macrolide from the edible cyanobacterium Aphanothece sacrum

• Naoya Oku,
• Miyako Matsumoto,
• Kohsuke Yonejima,
• Keijiroh Tansei and
• Yasuhiro Igarashi

Beilstein J. Org. Chem. 2014, 10, 1808–1816, doi:10.3762/bjoc.10.190

• . Antimicrobial testing against four Gram-positive bacteria (Bacillus subtilis, Micrococcus luteus, Staphylococcus aureus, and Streptomyces lividans), one Gram-negative bacterium (Escherichia coli), two yeasts (Candida albicans and Saccharomyces cerevisiae), and two fungi (Aspergillus oryzae and Penicillum

• strains were grown on agar media (Staphylococcus aureus FDA209P JC-1, Micrococcus luteus ATCC9341, Escherichia coli NIHJ JC-2, Saccharomyces cerevisiae S100, and Candida albicans A9540) or in Sabouraud broth (Penicillum chrysogenum NBRC4626, Streptomyces lividans TK23) overnight and then diluted with

Heronapyrrole D: A case of co-inspiration of natural product biosynthesis, total synthesis and biodiscovery

• Jens Schmidt,
• Zeinab Khalil,
• Robert J. Capon and
• Christian B. W. Stark

Beilstein J. Org. Chem. 2014, 10, 1228–1232, doi:10.3762/bjoc.10.121

• activity against the Gram-positive bacteria Staphylococcus aureus ATCC 25923 (IC50 1.8 μM), Staphylococcus epidermidis ATCC 12228 (IC50 0.9 μM) and Bacillus subtilis ATCC 6633 (IC50 1.8 μM), but was inactive (IC50 > 30 μM) against the Gram-negative bacteria Pseudomonas aeruginosa ATCC 10145 and Escherichia

• coli ATCC 25922, and the fungus Candida albicans ATCC 90028. Conclusion In conclusion, this study illustrates the importance of biosynthetic considerations to both natural products and synthetic chemistry. Biosynthetic hypotheses provide natural product chemists with a framework to challenge the

Physalin H from Solanum nigrum as an Hh signaling inhibitor blocks GLI1–DNA-complex formation

• Midori A. Arai,
• Kyoko Uchida,
• Samir K. Sadhu,
• Firoj Ahmed and
• Masami Ishibashi

Beilstein J. Org. Chem. 2014, 10, 134–140, doi:10.3762/bjoc.10.10

• assay (EMSA) for the detection of the GLI1–DNA complex. The assay uses a slightly modified biotin-tagged DNA and modified amino acids sequences of GLI1 compared to those reported in literature [30][31][32]. In a similar manner as described in [22], GLI1 protein was expressed in Escherichia coli as a 171

Biosynthesis of rare hexoses using microorganisms and related enzymes

• Zijie Li,
• Yahui Gao,
• Hideki Nakanishi,
• Xiaodong Gao and
• Li Cai

Beilstein J. Org. Chem. 2013, 9, 2434–2445, doi:10.3762/bjoc.9.281

• ], including the previously mentioned immobilized galactose oxidase [83][84], but the yields were generally low. In contrast, whole cells of recombinant Escherichia coli carrying a unique mannitol dehydrogenase (EC 1.1.1.255) represent a more scalable system [90] for oxidizing galactitol (Scheme 15

• effective precursor of the L-ascorbate synthesis [87]. Leang et al. established an efficient two-step method for synthesizing L-galactose on a large scale from a common sugar L-sorbose, catalyzed by immobilized DTEase from a mutant Pseudomonas sp. ST-24 and recombinant L-rhamnose isomerase from Escherichia

• coli JM109 [88]. L-Sorbose was first epimerized by DTEase at C-3 to give L-tagatose (28% yield), which reached an equilibrium with L-galactose (~30%) catalyzed by the L-rhamnose isomerase (Scheme 15). L-Galactose was also directly synthesized by oxidizing galactitol using D-galactose oxidase [89

Synthesis of enantiomerically pure (2S,3S)-5,5,5-trifluoroisoleucine and (2R,3S)-5,5,5-trifluoro-allo-isoleucine

• Holger Erdbrink,
• Elisabeth K. Nyakatura,
• Susanne Huhmann,
• Ulla I. M. Gerling,
• Dieter Lentz,
• Beate Koksch and
• Constantin Czekelius

Beilstein J. Org. Chem. 2013, 9, 2009–2014, doi:10.3762/bjoc.9.236

• isoleucine surrogates for protein synthesis in Escherichia coli [11][12]. Moreover, studying the impact of global Ile substitution with 5-F3Ile in comparison to the substitution of Val by 4,4,4-trifluorovaline (4-F3Val) through protein expression, they showed that the replacement of the δ-CH3 group of Ile by

Synthesis and antibacterial activity of monocyclic 3-carboxamide tetramic acids

• Yong-Chul Jeong and
• Mark G. Moloney

Beilstein J. Org. Chem. 2013, 9, 1899–1906, doi:10.3762/bjoc.9.224

• influenzae, including an efflux-negative strain, and 2 strains of Escherichia coli, including an efflux-negative strain (Table 2). Relevant physicochemical properties of the analogues are also shown in Table 3. These were used to elaborate structure–activity relationships (SAR) [26]. In the assay against

Straightforward synthesis of a tetrasaccharide repeating unit corresponding to the O-antigen of Escherichia coli O16

• Manas Jana and
• Anup Kumar Misra

Beilstein J. Org. Chem. 2013, 9, 1757–1762, doi:10.3762/bjoc.9.203

• Manas Jana Anup Kumar Misra Bose Institute, Division of Molecular Medicine, P-1/12, C.I.T. Scheme VII-M, Kolkata-700054, India, Fax: 91-33-2355 3886 10.3762/bjoc.9.203 Abstract A straightforward synthesis of the tetrasaccharide repeating unit of the O-antigen of Escherichia coli O16 has been

• stereoselective. Keywords: Escherichia coli; glycosylation; lipopolysaccharide; O-antigen; tetrasaccharide; Introduction Neonatal meningitis is a serious concern in developing countries [1]. The symptoms associated with this disease are unspecific and may ultimately lead to sepsis [2]. The common cause of the

• neonatal meningitis are bacterial infections in blood, and they start with the bacteria colonizing the gastrointestinal tract [3][4]. Microorganisms associated with neonatal meningitis are Streptococcus, Escherichia coli (E. coli) and Listeria monocytogenes [5][6]. Major E. coli strains causing neonatal

Synthesis and biological activities of the respiratory chain inhibitor aurachin D and new ring versus chain analogues

• Xu-Wen Li,
• Jennifer Herrmann,
• Yi Zang,
• Philippe Grellier,
• Soizic Prado,
• Rolf Müller and
• Bastien Nay

Beilstein J. Org. Chem. 2013, 9, 1551–1558, doi:10.3762/bjoc.9.176

• previous reports [1], antibacterial activities (Table 4) were mainly observed on Gram-positive bacteria while Gram-negative bacteria were not affected, except Escherichia coli TolC which is deficient in the corresponding multidrug efflux transporter. The tested compounds were neither active on yeast

Multivalent display of the antimicrobial peptides BP100 and BP143

• Imma Güell,
• Rafael Ferre,
• Kasper K. Sørensen,
• Esther Badosa,
• Iteng Ng-Choi,
• Emilio Montesinos,
• Eduard Bardají,
• Lidia Feliu,
• Knud J. Jensen and
• Marta Planas

Beilstein J. Org. Chem. 2012, 8, 2106–2117, doi:10.3762/bjoc.8.237

• phytopathogenic bacteria Erwinia amylovora, Xanthomonas axonopodis pv. vesicatoria, and Pseudomonas syringae pv. syringae, and of human pathogenic bacteria Escherichia coli, Staphylococcus aureus, Lysteria monocytogenes, and Salmonella enterica at 0.6, 1.2, 2.5, 5, 7.5, 10 and 20 μM (Table 1). The antibacterial

• Tecnologia Agroalimentària, Universitat de Girona, Spain), and Xanthomonas axonopodis pv. vesicatoria 2133-2 (Instituto Valenciano de Investigaciones Agrarias, Valencia, Spain). Moreover, the following bacterial strains were also used: Escherichia coli ATCC NCTC 5934, Listeria monocytogenes ATCC 15313

Convergent synthesis of the tetrasaccharide repeating unit of the cell wall lipopolysaccharide of Escherichia coli O40

• Abhijit Sau and
• Anup Kumar Misra

Beilstein J. Org. Chem. 2012, 8, 2053–2059, doi:10.3762/bjoc.8.230

• yielding and stereoselective. Keywords: Escherichia coli; glycosylation; lipopolysaccharide; O-antigen; tetrasaccharide; Introduction Infantile diarrhoea is one of the major causes of morbidity and mortality in infancy in developing countries [1]. Among several factors, Escherichia coli (E. coli

• , 43.14; H, 6.45. Structure of the tetrasaccharide repeating unit of the cell-wall lipopolysaccharide of Escherichia coli O40. Structure of the synthesized tetrasaccharide 1 and its synthetic precursors. Synthesis of disaccharide derivative 8. Reagents and conditions: (a) benzyl bromide, NaOH, DMF, room

Modulating the activity of short arginine-tryptophan containing antibacterial peptides with N-terminal metallocenoyl groups

• H. Bauke Albada,
• Alina-Iulia Chiriac,
• Michaela Wenzel,
• Maya Penkova,
• Julia E. Bandow,
• Hans-Georg Sahl and
• Nils Metzler-Nolte

Beilstein J. Org. Chem. 2012, 8, 1753–1764, doi:10.3762/bjoc.8.200

• activity against Gram-negative Escherichia coli much more than against Gram-positive Bacillus subtilis [30][31], and only slightly increased the hemolytic activity [32]. Moreover, the alkylation of tryptophan residues by tert-butyl groups resulted in increased activity and low hemolytic activity of the

• in Table 2) The minimal inhibitory concentrations (MIC) were tested against Escherichia coli DSM 30083, Acinetobacter baumannii DSM 30007, Pseudomonas aeruginosa DSM 50071, Bacillus subtilis DSM 402, Staphylococcus aureus DSM 20231 (type strain), and Staphylococcus aureus ATCC 43300 (MRSA) in a

Partial thioamide scan on the lipopeptaibiotic trichogin GA IV. Effects on folding and bioactivity

• Marta De Zotti,
• Barbara Biondi,
• Cristina Peggion,
• Matteo De Poli,
• Haleh Fathi,
• Simona Oancea,
• Claudio Toniolo and
• Fernando Formaggio

Beilstein J. Org. Chem. 2012, 8, 1161–1171, doi:10.3762/bjoc.8.129

• , Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Klebsiella pneumoniae ATCC 13883, Salmonella entereditis 13076, and Proteus mirabilis ATCC 10975. The well-known antibiotics bacitracin and tetracyclin (10 μg/disk) were used as controls. List of primary structures and abbreviations for the