RESUMO
The salinosporamides are potent proteasome inhibitors among which the parent marine-derived natural product salinosporamide A (marizomib; NPI-0052; 1) is currently in clinical trials for the treatment of various cancers. Methods to generate this class of compounds include fermentation and natural products chemistry, precursor-directed biosynthesis, mutasynthesis, semi-synthesis, and total synthesis. The end products range from biochemical tools for probing mechanism of action to clinical trials materials; in turn, the considerable efforts to produce the target molecules have expanded the technologies used to generate them. Here, the full complement of methods is reviewed, reflecting remarkable contributions from scientists of various disciplines over a period of 7 years since the first publication of the structure of 1.
Assuntos
Inibidores Enzimáticos/farmacologia , Lactonas/farmacologia , Inibidores de Proteassoma , Pirróis/farmacologia , Animais , Desenho de Fármacos , Fermentação , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/enzimologia , Tecnologia Farmacêutica/métodosRESUMO
Large-scale fermentation of the marine actinomycete Salinispora tropica for production of salinosporamide A (NPI-0052; 1) clinical trials materials provided crude extracts containing minor secondary metabolites, including salinosporamide B (2) and a new congener, 3. Spectroscopic characterization revealed that 3 is identical to antiprotealide, a molecular hybrid of 20S proteasome inhibitors 1 and omuralide (4) not previously described as a natural product. Analysis of crude extracts from shake flask cultures of three wild-type S. tropica strains confirmed the production of antiprotealide at 1.1, 0.8, and 3.0 mg/L. Thus, antiprotealide is a natural product metabolite of S. tropica.
Assuntos
Actinobacteria/química , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Lactamas/química , Lactamas/isolamento & purificação , Lactonas/química , Lactonas/isolamento & purificação , Pirróis/química , Pirróis/isolamento & purificação , Animais , Produtos Biológicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Concentração Inibidora 50 , Lactamas/farmacologia , Lactonas/farmacologia , Biologia Marinha , Estrutura Molecular , Complexo de Endopeptidases do Proteassoma , Pirróis/farmacologia , CoelhosRESUMO
The discovery of the anticancer agent salinosporamide A (NPI-0052) resulted from the exploration of new marine environments and a commitment to the potential of the ocean to yield new natural products for drug discovery and development. Driving the success of this process was the linkage of academic research together with the ability and commitment of industry to undertake drug development and provide the resources and expertise to advance the entry of salinosporamide A (NPI-0052) into human clinical trials. This paper offers a chronicle of the important events that facilitated the rapid clinical development of this exciting molecule.
Assuntos
Antineoplásicos/química , Descoberta de Drogas , Lactonas/química , Pirróis/química , Drogas em Investigação , Estrutura MolecularRESUMO
A series of chlorinated bisindole pyrroles, lynamicins A-E (1-5), was discovered from a novel marine actinomycete, NPS12745, which was isolated from a marine sediment collected off the coast of San Diego, California. Close to full length 16S rRNA sequence analysis indicated that NPS12745 is a novel strain of a recently described marine actinomycete with the proposed genus name Marinispora. The antimicrobial spectrum of these compounds was evaluated against a panel of 11 pathogens, which demonstrated that these substances possess broad-spectrum activity against both Gram-positive and Gram-negative organisms. Significantly, compounds 1-5 were active against drug-resistant pathogens such as methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus faecium.
Assuntos
Actinobacteria/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Hidrocarbonetos Clorados/isolamento & purificação , Hidrocarbonetos Clorados/farmacologia , Indóis/isolamento & purificação , Indóis/farmacologia , Pirróis/isolamento & purificação , Pirróis/farmacologia , Actinobacteria/genética , Antibacterianos/química , California , Farmacorresistência Bacteriana/efeitos dos fármacos , Enterococcus faecium/efeitos dos fármacos , Hidrocarbonetos Clorados/química , Indóis/química , Biologia Marinha , Resistência a Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Pirróis/química , Staphylococcus aureus/efeitos dos fármacos , Resistência a Vancomicina/efeitos dos fármacosRESUMO
We recently described the development of a potassium-chloride-based salt formulation containing low sodium concentration (5.0 mM) to support the growth of Salinispora tropica strain NPS21184 and its production of salinosporamide A (NPI-0052). In order to determine whether the above low-sodium salt formulation can also support the growth of other S. tropica strains, we examined the growth of the type strain CNB440 and the parent strain CNB476, from which strain NPS21184 was derived as a single colony isolate. We demonstrated that good growth rate and yield of S. tropica strains CNB440 and CNB476, similar to S. tropica strain NPS21184 reported earlier, were detected in both agar and liquid media containing the potassium-chloride-based salt formulation with sodium concentration of 5.0 mM. Furthermore, we also detected good growth rate and yield of all three S. tropica strains on potassium-sulfate-based salt formulation agar medium containing both low-sodium (5.7 mM) and low-chloride (14 mM) content. This finding confirms the observation that the species of S. tropica does not have a seawater growth requirement but requirement for a specific combination of salts to provide a balance of salts and maintain a high enough ionic strength for growth.
Assuntos
Meios de Cultura/química , Meios de Cultura/metabolismo , Micromonosporaceae/crescimento & desenvolvimento , Micromonosporaceae/metabolismo , Água do Mar/microbiologia , Cloreto de Sódio/metabolismo , Lactonas , Micromonosporaceae/isolamento & purificação , PirróisRESUMO
In order to improve aqueous solubility of nocathiacin I (1), a potent antibacterial agent, N-demethylation of the amino-sugar moiety was sought. Irradiation of 1 in DMF/CH(2)Cl(2) with UV light of 380 nm led to a cyclic product 2, which was hydrolyzed to yield the desired nocathiacin VI (3). Treatment of 1 with shorter UV light caused trans-cis isomerization of a c-c double bond.
Assuntos
Oxigênio/química , Peptídeos/química , Anti-Infecciosos/farmacologia , Química Farmacêutica/métodos , Desenho de Fármacos , Hidrólise , Peptídeos e Proteínas de Sinalização Intercelular , Luz , Metilação , Modelos Químicos , Estrutura Molecular , Oxirredução , Solubilidade , Solventes/química , Relação Estrutura-Atividade , Raios UltravioletaRESUMO
A novel marine actinomycete strain NPS8920 produces a new class of 4-oxazolidinone antibiotics lipoxazolidinone A, B and C. Lipoxazolidinone A possesses good potency (1-2 microg/mL) against drug-resistant pathogens methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus faecium (VRE). Strain NPS8920 exhibits different morphologies in both agar and submerged cultures. The ability of strain NPS8920 to sporulate on saline-based agar media but not on deionized water-based agar medium supported that strain NPS8920 is a marine actinomycete. While strain NPS8920 does not require seawater for growth, the production of lipoxazolidinones by strain NPS8920 can only be detected in the seawater-based media. The optimal production of lipoxazolidinones was observed in the natural seawater-based medium. Strain NPS8920 produced 10-20% of lipoxazolidinones in the synthetic sea salt Instant Ocean-based medium and no production in the sodium chloride-based and deionized water-based media.
Assuntos
Actinobacteria/crescimento & desenvolvimento , Actinobacteria/metabolismo , Antibacterianos/metabolismo , Oxazolidinonas/metabolismo , Água do Mar/microbiologia , Meios de Cultura/química , Estrutura MolecularRESUMO
Salinosporamide A (NPI-0052) is currently produced by a marine actinomycete, Salinispora tropica, via a saline fermentation process using a non-defined, commercially available synthetic sea salt, Instant Ocean. In order to control the consistency of the production of NPI-0052 and related analogs, two chemically defined salt formulations were developed to replace Instant Ocean. A chemically defined sodium-chloride-based salt formulation with similar sodium and chloride contents as in Instant Ocean was found to support higher production of NPI-0052 and a better metabolite production profile for downstream processing than Instant Ocean. A chemically defined sodium-sulfate-based salt formulation with low chloride concentration at 17 mM was found to support a similar NPI-0052 and metabolite production profile as Instant Ocean. The sodium-sulfate-based formulation is a robust formulation for large-scale production process due to its reduced corrosiveness in fermentation as compared with the saline fermentation utilizing Instant Ocean or the sodium-chloride-based salt formulation. The production of NPI-0052 in both chemically defined salt formulations was successfully scaled-up to a 42-l fermentor, indicating that these salt formulations can be used for large-scale manufacturing process.
Assuntos
Meios de Cultura/química , Lactonas/metabolismo , Micromonosporaceae/metabolismo , Pirróis/metabolismo , Cloreto de Sódio/metabolismo , Sedimentos Geológicos/microbiologia , Microbiologia Industrial , Lactonas/química , Espectrometria de Massas , Micromonosporaceae/crescimento & desenvolvimento , Pirróis/química , Cloreto de Sódio/análiseRESUMO
In this paper, we described the development of a potassium-chloride-based-salt formulation containing low sodium concentrations (5.0 to 11 mM) to support the growth of Salinispora tropica strain NPS21184 and its production of salinosporamide A (NPI-0052). The sodium present in the media was essentially derived from the complex nitrogen sources Hy Soy, yeast extract, and peptone used in the media. We demonstrated that good growth rate and yield of S. tropica strain NPS21184 were detected in both agar and liquid media containing the potassium-chloride-based-salt formulation with sodium concentration as low as 5.0 mM, significantly less than the critical seawater-growth requirement concentration of 50 mM sodium for a marine microorganism. We also observed good production of NPI-0052 (176 to 243 mg/l) by S. tropica strain NPS21184 grown in production media containing the potassium chloride-based-salt formulation. The production of deschloro analog, salinosporamide B (NPI-0047), was significantly lower in the low-sodium-salt-formulation medium than in the high-sodium-salt-formulation media. We demonstrated that while S. tropica strain NPS21184 is a novel marine actinomycete that requires high salt content for growth, it does not require sodium-chloride-based seawater-type media for growth and production of NPI-0052.
Assuntos
Meios de Cultura/química , Fermentação , Microbiologia Industrial , Lactonas/metabolismo , Micromonosporaceae/metabolismo , Pirróis/metabolismo , Compostos de Sódio/metabolismo , Lactamas/metabolismo , Micromonosporaceae/crescimento & desenvolvimento , Água do Mar/microbiologiaRESUMO
Marine actinomycete strain NPS008920, a member of the new genus Marinispora, was isolated from a sediment sample collected in Cocos Lagoon, Guam. In natural sea water containing media, the strain produced a series of novel 2-alkylidene-5-alkyl-4-oxazolidinones, lipoxazolidinone A (1), B (2), and C (3). Compounds 1- 3 showed broad spectrum antimicrobial activity similar to that of the commercial antibiotic linezolid (Zyvox), a 2-oxazolidinone. Hydrolysis of the amide bond of the 4-oxazolidinone ring of 1 resulted in loss of antibacterial activity. The 2-alkylidene-4-oxazolidinone represents a new antibiotic pharmacophore and is unprecedented in nature.
Assuntos
Actinobacteria/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Oxazolidinonas/isolamento & purificação , Oxazolidinonas/farmacologia , Antibacterianos/química , Guam , Haemophilus influenzae/efeitos dos fármacos , Biologia Marinha , Estrutura Molecular , Oxazolidinonas/química , Relação Estrutura-AtividadeRESUMO
Addition of acrylic resin Amberlite XAD-7 during the fermentation of Salinispora tropica significantly enhanced the production of NPI-0052 by 69 fold. Examination of the time course of resin addition to the Salinispora tropica fermentation demonstrated that the increase in the production of NPI-052 is due to the stabilization effect by resin but not the removal of an end product feedback repression. Delay in resin addition to the fermentation led to decreases in the production of NPI-0052 to the amounts that are synthesized prior to the resin addition.
Assuntos
Resinas Acrílicas/farmacologia , Resinas de Troca Aniônica/farmacologia , Fermentação , Lactonas/farmacologia , Micromonosporaceae/metabolismo , Poliestirenos/farmacologia , Inibidores de Proteases/farmacologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Pirróis/farmacologia , Apoptose/efeitos dos fármacos , Fermentação/efeitos dos fármacos , Humanos , Micromonosporaceae/enzimologia , Inibidores de ProteassomaRESUMO
During the past 15 years, most large pharmaceutical companies have decreased the screening of natural products for drug discovery in favor of synthetic compound libraries. Main reasons for this include the incompatibility of natural product libraries with high-throughput screening and the marginal improvement in core technologies for natural product screening in the late 1980s and early 1990 s. Recently, the development of new technologies has revolutionized the screening of natural products. Applying these technologies compensates for the inherent limitations of natural products and offers a unique opportunity to re-establish natural products as a major source for drug discovery. Examples of these new advances and technologies are described in this review.
Assuntos
Anti-Infecciosos , Antineoplásicos , Fatores Biológicos , Animais , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/metabolismo , Anti-Infecciosos/uso terapêutico , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/uso terapêutico , Bactérias/metabolismo , Fatores Biológicos/química , Fatores Biológicos/isolamento & purificação , Fatores Biológicos/metabolismo , Fatores Biológicos/uso terapêutico , Biotecnologia/tendências , Ensaios Clínicos como Assunto , Doenças Transmissíveis/tratamento farmacológico , Avaliação Pré-Clínica de Medicamentos , Fungos/metabolismo , HumanosRESUMO
Feeding sodium butyrate (0.25-1 mg/ml) to cultures of Salinispora tropica NPS21184 enhanced the production of salinosporamide B (NPI-0047) by 319% while inhibiting the production of salinosporamide A (NPI-0052) by 26%. Liquid chromatography mass spectrometry analysis of the crude extract from the strain NPS21184 fed with 0.5 mg/ml sodium [U-(13)C(4)]butyrate indicated that butyrate was incorporated as a contiguous four-carbon unit into NPI-0047 but not into NPI-0052. Nuclear magnetic resonance analysis of NPI-0047 and NPI-0052 purified from the sodium [U-(13)C(4)]butyrate-supplemented culture extract confirmed this incorporation pattern. The above finding is the first direct evidence to demonstrate that the biosynthesis of NPI-0047 is different from NPI-0052, and NPI-0047 is not a precursor of NPI-0052.
Assuntos
Ácido Butírico/química , Lactamas/química , Lactonas/química , Pirróis/química , Lactamas/metabolismo , Lactonas/metabolismo , Espectroscopia de Ressonância Magnética , Micromonosporaceae/metabolismo , Pirróis/metabolismoRESUMO
We examined the effects of halogens on the production of salinosporamide A (NPI-0052) by the obligate marine actinomycete Salinispora tropica NPS465, specifically the production of analogs containing halogens other than chlorine. Adding NaF, NaBr and NaI directly to the production medium prepared in seawater containing -3% NaCl did not induce the production of the corresponding analogs. Replacing seawater with 2-3% NaI in the production medium enhanced the production of NPI-0052 by 2.1 fold. Replacing seawater with 2-3% NaBr in the production medium suppressed the production of NPI-0052 but induced the production of a brominated analog at very low yield. Using a stepwise enrichment of bromide in the seed cultures in order to reduce the chloride ion carried over to the production medium, the production of the brominated analog was enhanced by 4 fold. We also demonstrated that the growth of this obligate marine actinomycete is dependent upon sodium concentration, not chloride concentration.
Assuntos
Actinomycetales/metabolismo , Brometos/farmacologia , Lactonas/química , Lactonas/metabolismo , Pirróis/química , Pirróis/metabolismo , Compostos de Sódio/farmacologia , Fluoreto de Sódio/farmacologia , Iodeto de Sódio/farmacologia , Actinomycetales/efeitos dos fármacos , Actinomycetales/crescimento & desenvolvimento , Cromatografia Líquida de Alta Pressão , Meios de Cultura/química , Lactonas/isolamento & purificação , Estrutura Molecular , Pirróis/isolamento & purificaçãoRESUMO
Salinosporamide A (NPI-0052; 3), a highly potent inhibitor of the 20S proteasome, is currently in phase I clinical trials for the treatment of cancer. During the course of purifying multigram quantities of 3 from Salinispora tropica fermentation extracts, several new salinosporamides were isolated and characterized, most of which represent modifications to the chloroethyl substituent at C-2. Specifically, 3 was isolated along with the known compound salinosporamide B (4), the previously undescribed methyl congener salinosporamide D (7), and C-2 epimers of 3 and 7 (salinosporamides F (9) and G (10), respectively). Salinosporamide I (13), in which the methyl group at the ring junction is replaced with an ethyl group, and the C-5 deshydroxyl analogue salinosporamide J (14), were also identified. Replacement of synthetic sea salt with sodium bromide in the fermentation media produced bromosalinosporamide (12), 4, and its C-2 epimer (11, salinosporamide H). In addition to these eight new salinosporamides, several thioester derivatives were generated semisynthetically. IC50 values for cytotoxicity against human multiple myeloma cell line RPMI 8226 and inhibition of the chymotrypsin-like (CT-L) activity of purified rabbit 20S proteasomes were determined for all compounds. The results indicate that thioesters may directly inhibit the proteasome, albeit with reduced potency compared to their beta-lactone counterparts.
Assuntos
Actinobacteria/química , Lactonas , Inibidores de Proteassoma , Pirróis , Actinobacteria/crescimento & desenvolvimento , Bahamas , Cristalografia por Raios X , Concentração Inibidora 50 , Lactonas/química , Lactonas/isolamento & purificação , Lactonas/farmacologia , Biologia Marinha , Conformação Molecular , Estrutura Molecular , Pirróis/química , Pirróis/isolamento & purificação , Pirróis/farmacologiaRESUMO
Recent findings from culture-dependent and culture-independent methods have demonstrated that indigenous marine actinomycetes exist in the oceans and are widely distributed in different marine ecosystems. There is tremendous diversity and novelty among the marine actinomycetes present in marine environments. Progress has been made to isolate novel actinomycetes from samples collected at different marine environments and habitats. These marine actinomycetes produce different types of new secondary metabolites. Many of these metabolites possess biological activities and have the potential to be developed as therapeutic agents. Marine actinomycetes are a prolific but underexploited source for the discovery of novel secondary metabolites.
Assuntos
Actinobacteria/metabolismo , Antibacterianos/metabolismo , Antifúngicos/metabolismo , Antineoplásicos/metabolismo , Água do Mar/microbiologia , Actinobacteria/classificação , Antibacterianos/química , Antifúngicos/química , Antineoplásicos/químicaRESUMO
Stereoselective reduction of dehydroalanine double bond in nocathiacin I afforded the primary amide 2. Enzymatic hydrolysis of the amide 2 provided the carboxylic acid 3, which upon coupling with a variety of amines furnished amides 4-32. Some of these semi-synthetic derivatives have retained very good antibacterial activity and have improved aqueous solubility.
Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Enterococcus faecalis/efeitos dos fármacos , Peptídeos/síntese química , Peptídeos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Streptococcus pneumoniae/efeitos dos fármacos , Antibacterianos/química , Técnicas In Vitro , Peptídeos e Proteínas de Sinalização Intercelular , Testes de Sensibilidade Microbiana , Estrutura Molecular , Peptídeos/química , Solubilidade , Estereoisomerismo , Relação Estrutura-Atividade , Água/químicaRESUMO
Natural product compounds are the source of numerous therapeutic agents. Recent progress to discover drugs from natural product sources has resulted in compounds that are being developed to treat cancer, resistant bacteria and viruses and immunosuppressive disorders. Many of these compounds were discovered by applying recent advances in understanding the genetics of secondary metabolism in actinomycetes, exploring the marine environment and applying new screening technologies. In many instances, the discovery of a novel natural product serves as a tool to better understand targets and pathways in the disease process. This review describes recent progress in drug discovery from natural sources including several examples of compounds that inhibit novel drug targets.
Assuntos
Bactérias/metabolismo , Produtos Biológicos/biossíntese , Produtos Biológicos/química , Avaliação Pré-Clínica de Medicamentos/métodos , Preparações Farmacêuticas/isolamento & purificação , Animais , Bactérias/genética , Produtos Biológicos/genética , Preparações Farmacêuticas/químicaRESUMO
The solid-phase synthesis of a library based on the natural product anisomycin is described. The resulting library was tested against a panel of bacterial and fungal targets, and active compounds were identified in a Staphylococcus aureus whole-cell assay and an efflux-deficient fungal whole-cell assay.
Assuntos
Anisomicina/química , Anti-Infecciosos/síntese química , Anti-Infecciosos/farmacologia , Produtos Biológicos/química , Técnicas de Química Combinatória , Anti-Infecciosos/química , Linhagem Celular , Fungos/citologia , Fungos/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Estrutura Molecular , Staphylococcus aureus/citologia , Staphylococcus aureus/efeitos dos fármacos , Relação Estrutura-AtividadeRESUMO
A Streptomyces sp. (NPS008187) isolated from a marine sediment collected in Alaska was found to produce three new pyrrolosesquiterpenes, glyciapyrroles A (1), B (2), and C (3), along with the known diketopiperazines cyclo(leucyl-prolyl) (4), cyclo(isoleucyl-prolyl) (5), and cyclo(phenylalanyl-prolyl) (6). The structures of 1, 2, and 3 were established using spectroscopic methods.