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1.
Intern Med ; 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38960683

RESUMEN

We herein report a 67-year-old Japanese woman with liver cirrhosis caused by primary biliary cholangitis. The patient was admitted to the hospital with loss of consciousness. Hepatic encephalopathy (HE) was diagnosed after diagnostic imaging and symptom assessments. Molecular biology tests were performed on oral saliva and stool samples. The test results indicated sequence similarity between urease-positive S. salivarius in both oral saliva and stool, as revealed by the signals in the overlapping peaks. This bacterium can potentially increase ammonia production in the gut, leading to HE in patients with liver cirrhosis.

2.
Dig Dis ; 42(1): 61-69, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37769624

RESUMEN

INTRODUCTION: Limited data are available on the correlation between microbial communities and metabolic dysfunction-associated fatty liver disease (MAFLD). This study aimed to evaluate the influence of MAFLD on diverse microbial communities. METHODS: We recruited 43 patients with a nonviral liver disease. Enrolled patients were divided into two groups according to MAFLD criteria. The fecal microbial composition was evaluated using the variable V3-V4 region of the 16S ribosomal RNA region, which was amplified using polymerase chain reaction. First, we assessed the influence of MAFLD on distinct microbial communities at the bacterial phylum level. Next, the correlation between the microbial communities and diversity in patients with MAFLD was evaluated. RESULTS: Among the enrolled participants, the non-MAFLD and MAFLD groups consisted of 21 and 22 patients, respectively. Sequences were distributed among ten bacterial phyla. The relative abundance of Firmicutes was significantly higher in the MAFLD group than in the non-MAFLD group (p = 0.014). The microbial diversity was not significantly influenced by the presence of MAFLD (Chao-1 index: p = 0.215 and Shannon index: p = 0.174, respectively); nonetheless, the correlation coefficient between the abundances of Firmicutes and microbial diversity was higher in the non-MAFLD group than in the MAFLD group. CONCLUSION: The presence of MAFLD increased the relative abundances of Firmicutes at the bacterial phylum level, which may cause the discrepancy between the abundances of Firmicutes and diversity in patients with MAFLD.


Asunto(s)
Microbiota , Enfermedad del Hígado Graso no Alcohólico , Humanos , Heces
3.
Eur J Gastroenterol Hepatol ; 35(8): 865-873, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37395239

RESUMEN

OBJECTIVE: To investigate the association between body composition and prognosis in patients with advanced hepatocellular carcinoma treated with atezolizumab plus bevacizumab. METHODS: This cohort study analysed 119 patients who received atezolizumab plus bevacizumab for unresectable hepatocellular carcinoma. We investigated the association between body composition and progression-free survival and overall survival. Body composition was quantified by the visceral fat index, subcutaneous fat index, and skeletal muscle index. A high or low index score was defined as that above or below the median of these indices. RESULTS: Poor prognosis was observed in the low visceral fat index and low subcutaneous fat index groups. The mean progression-free survival in the low visceral fat index and low subcutaneous fat index groups vs. the other groups were 194 and 270 days, respectively [95% confidence interval (CI), 153-236 and 230-311 days, respectively; P = 0.015], while the mean overall survival was 349 vs. 422 days, respectively (95% CI, 302-396 and 387-458 days, respectively; P = 0.027). In the multivariate analysis, both a low subcutaneous fat index and low visceral fat index were statistically associated with lower progression-free and overall survival rates [hazard ratio (HR) 1.721; 95% CI, 1.101-2.688; P = 0.017; and HR 2.214; 95% CI, 1.207-4.184; P = 0.011, respectively]. CONCLUSION: Low visceral fat index and subcutaneous fat index scores were independent predictors of poor prognosis in patients with unresectable hepatocellular carcinoma treated with atezolizumab plus bevacizumab.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Bevacizumab/efectos adversos , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/inducido químicamente , Estudios de Cohortes , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/inducido químicamente , Composición Corporal
4.
Hepatol Res ; 53(10): 998-1007, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37279155

RESUMEN

AIM: We performed genomic analysis to study the relative abundance of a urease-positive Streptococcus salivarius group isolated from the saliva of patients with chronic liver disease. METHODS: Male and female patients with chronic liver disease aged over 20 years were included. First, we assessed the frequency and type of the S. salivarius group isolated from oral saliva using molecular biology techniques based on 16S rRNA and dephospho-coenzyme A kinase gene sequencing. Next, we assessed the correlation between the urease positivity rate in the S. salivarius group isolated from oral saliva and liver fibrosis based on chronic liver disease. Urease-positive strains were identified by the urease test using urea broth (Difco, Franklin Lakes, NJ, USA). Liver fibrosis was evaluated by the liver stiffness measurement value based on magnetic resonance elastography. RESULTS: A total of 45 patients identified using the multiplex polymerase chain reaction for the 16S rRNA gene were tested using the multiplex polymerase chain reaction for the dephospho-coenzyme A kinase gene. Confirming the strains detected in each of the 45 patients, urease-positive S. salivarius was detected in 28 patients (62%), urease-negative S. salivarius in 25 patients (56%), and urease-positive Streptococcus vestibularis in 12 patients (27%). There was no patient with urease-negative S. vestibularis. The urease-positive rate of the S. salivarius group in the cirrhosis and non-cirrhosis groups were 82.2% and 39.2%, respectively. The liver cirrhosis group had a higher urease positivity rate than the non-cirrhotic group (p < 0.001). CONCLUSIONS: Liver fibrosis influences the frequency of a urease-positive S. salivarius group isolated from oral saliva.

5.
Artículo en Inglés | MEDLINE | ID: mdl-36961876

RESUMEN

An actinomycete strain K14-0274T was isolated from the root of Arisaema thunbergii Blume subsp. urashima (H. Hara) H. Ohashi et J. Murata collected in Japan. The results of phylogenetic analysis based on the 16S rRNA gene sequence indicated thatK14-0274T could be distinguished from the members of all known genera, although it represented a member of the family Streptosporangiaceae. K14-0274T produced sporangium-like spherical vesicles with spores on white aerial mycelia. MK-9 (H4) and MK-9 (H6) were the major menaquinones. The whole-cell hydrolysates contained madurose, glucose, mannose, rhamnose and ribose. The cell-wall amino acids comprise l-alanine, d-alanine, d-glutamic acid and meso-diaminopimelic acid. The N-acyl type of muramic acid was acetyl. Mycolic acids were not detected. Phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylinositol and phosphatidylinositolmannoside were detected. The predominant fatty acids were iso-C16 : 0, 10-methyl-C18 : 0 and C16 : 0. The G+C content of the genomic DNA was 69.7 mol%. On the basis of morphological, phylogenetic and chemotaxonomic characteristics, strain K14-0427T represents a novel genus in the family Streptosporangiaceae, for which the name Rhizohabitans arisaemae gen. nov., sp. nov. is proposed. The type strain is K14-0247T (=NBRC 114594T =TBRC 12948T).


Asunto(s)
Actinobacteria , Actinomycetales , Ácidos Grasos/química , Fosfolípidos/química , Filogenia , ARN Ribosómico 16S/genética , ADN Bacteriano/genética , Composición de Base , Análisis de Secuencia de ADN , Técnicas de Tipificación Bacteriana , Vitamina K 2/química
6.
Artículo en Inglés | MEDLINE | ID: mdl-36951888

RESUMEN

A novel actinomycete, designated strain OK19-0408T, was isolated from soil collected on Iheya island, Okinawa prefecture, Japan. Using the polyphasic taxonomic approach, comparing 16S rRNA gene sequences, the new isolate was found to be most closely related to Amycolatopsis vancoresmycina JCM12675T (98.71 %). Phylogenetic analyses using 16S rRNA sequences indicated that strain OK19-0408T was clustered with Amycolatopsis australiensis JCM15587T. However, digital DNA-DNA hybridization analyses indicated a low relatedness, in the range of 33.9-34.7 %, between strain OK19-0408T and these closely related strains. Strain OK19-0408T contained meso-diaminopimelic acid and whole-cell sugars consisting of arabinose and galactose. The acyl type of the peptidoglycan was acetyl and mycolic acids were absent in strain OK19-0408T. The major menaquinone was MK-9(H4) and hydroxy-phosphatidylethanolamine was detected as the predominant phospholipid. The predominant cellular fatty acid was iso-C16 : 0. The DNA G+C content of the genomic DNA was 71.5 mol%. Based on the polyphasic approach, strain OK19-0408T represents a novel species of the genus Amycolatopsis, for which the name Amycolatopsis iheyensis sp. nov. is proposed. The type strain of the type species is OK19-0408T (=NBRC115671T=TBRC16040T).


Asunto(s)
Actinomycetales , Ácidos Grasos , Ácidos Grasos/química , Amycolatopsis , Filogenia , ARN Ribosómico 16S/genética , Japón , Suelo , ADN Bacteriano/genética , Composición de Base , Técnicas de Tipificación Bacteriana , Análisis de Secuencia de ADN , Microbiología del Suelo
7.
Appl Microbiol Biotechnol ; 107(1): 369-378, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36478282

RESUMEN

Streptomyces avermitilis is a gram-positive bacterium that undergoes complex physiological and morphological differentiation during its life cycle, which has implications in secondary metabolite production. Avermectin, produced by S. avermitilis, is widely used as an anthelmintic and insecticidal agent. In this study, we have applied Raman microspectroscopic imaging to elucidate the correlation between production of avermectin and the morphological differentiation in S. avermitilis. We demonstrate distinctive variations in the localization of secondary metabolites at various stages of morphological differentiation. Under solid culture, avermectin was detected in the mycelia formed at the later stages of morphological differentiation (e.g., spore-bearing mycelium and spiral spore chains), but not in the early-stage substrate mycelium. On the contrary, under liquid culture condition, avermectin was found concentrated in the mycelial pellet formed at the early MII stage of differentiation. Furthermore, the chemical profiles of the mycelia were substantially different depending on the culture condition. Raman spectra corresponding to proteins, lipids, and cytochrome were observed in the mycelia irrespective of the stage of morphological differentiation, however, carotenoid was observed under solid culture condition particularly in spore-bearing mycelium and spiral spore chains. KEY POINTS: • Avermectin production is regulated during mycelial differentiation • Liquid and solid culture conditions affects mycelial differentiation • Raman microspectroscopic analysis reveals localization profiles of avermectin.


Asunto(s)
Regulación Bacteriana de la Expresión Génica , Streptomyces , Streptomyces/metabolismo , Ivermectina , Micelio/metabolismo
8.
BMC Vet Res ; 18(1): 395, 2022 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-36352470

RESUMEN

BACKGROUND: Streptococcus canis causes deep pyoderma in canines, which raises concerns about the risk of isolates from lesions acquiring an antibiotic-resistant phenotype. It is necessary to identify effective antibiotics and the characteristics of the pathogenic cluster for S. canis-associated deep pyoderma. RESULTS: The signalment, molecular typing, and antibiotic-resistant status of S. canis isolated from deep pyoderma lesions (27 strains) and oral cavities (26 strains) were analyzed. Older dogs tended to have S. canis-associated deep pyoderma (15 of 27 dogs over 10 years old). Veterinarians chose quinolones for 10/16 cases (63%), even though the rate of quinolone-resistant strains of S. canis is 38-59%. Although 70% of the strains showed resistance to three or more antibiotic classes (37/53), 94% (50/53) strains showed sensitivity for penicillins. We also identified ß-lactamase activity among penicillin-resistant strains of S. canis. Clonal complex 13 (CC13) was detected only in lesions and formed independent clusters in the phylogenetic tree. One strain of CC13 was resistant to the anti-methicillin-resistant Staphylococcus aureus drugs, vancomycin and linezolid. CONCLUSION: Although antibiotic-resistant strains of S. canis are isolated at a high rate, they can currently be treated with ß-lactamase-inhibiting penicillins. CC13 may be a pathogenic cluster with high levels of antibiotics resistance.


Asunto(s)
Enfermedades de los Perros , Staphylococcus aureus Resistente a Meticilina , Piodermia , Infecciones Estafilocócicas , Perros , Animales , Piodermia/tratamiento farmacológico , Piodermia/veterinaria , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Staphylococcus aureus Resistente a Meticilina/genética , Pruebas de Sensibilidad Microbiana/veterinaria , Filogenia , Enfermedades de los Perros/tratamiento farmacológico , Penicilinas , beta-Lactamasas/genética , Infecciones Estafilocócicas/veterinaria
9.
Ann Nutr Metab ; 78(6): 336-344, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35981519

RESUMEN

OBJECTIVE: We aimed to evaluate the difference between computed tomography (CT)-based and bioelectrical impedance analysis (BIA)-based assessment of sarcopenia in patients with chronic liver disease (CLD). METHODS: We enrolled a total of 257 patients who were evaluated with or without sarcopenia. Sarcopenia was defined as a low skeletal muscle mass index (SMI) with low muscular strength by the Japan Society of Hepatology. To evaluate whether or not the different methods influence the diagnosis of sarcopenia for patients with CLD, we assessed the number and characteristics of mismatches between the low SMI using BIA and CT. We also compared the overall survival (OS) in patients with and without sarcopenia based on CT and BIA to evaluate the appropriate methods. RESULTS: The numbers of patients with low SMI using BIA or CT were 53 (20.6%) and 114 (44.3%) patients, respectively. Multivariate analysis revealed that hepatic ascites and body weight were independent factors of mismatch between SMI using BIA versus CT (hazard ratio [HR] 3.232, p < 0.001; HR 2.347, p = 0.005, respectively). The median OS in patients with sarcopenia based on CT was significantly lower than that in patients without sarcopenia (p = 0.006). In contrast, there was no difference between patients with sarcopenia based on BIA (p = 0.217). CONCLUSION: Muscle mass in patients with CLD may be overestimated by the BIA method compared to CT when assessing sarcopenia, especially in cases of fluid retention.


Asunto(s)
Hepatopatías , Humanos , Japón , Hepatopatías/complicaciones , Hepatopatías/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Músculo Esquelético/diagnóstico por imagen , Tomografía
10.
BMC Cancer ; 22(1): 912, 2022 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-35999529

RESUMEN

BACKGROUND: Lenvatinib is appropriate for reducing the production of nitric oxide (NO) and facilitating as block angiogenesis. However, to our knowledge, there are no data that support the correlation between NO and clinical response in patients who received lenvatinib therapy for HCC. Therefore, we investigated the correlation between the change rate of NO levels and clinical responses including adverse events (AEs) after lenvatinib therapy for unresectable hepatocellular carcinoma (HCC). METHODS: This study was conducted using previously collected data from another study. We enrolled 70 patients who received lenvatinib for advanced or unresectable HCC. NO was measured by converting nitrate (NO3-) to nitrite (NO2-) with nitrate reductase, followed by quantitation of NO2- based on Griess reagent. To determine whether lenvatinib influences NO in unresectable HCC, we evaluated the influence of the change rate of NO from baseline after administration of lenvatinib on maximal therapeutic response and SAE. RESULTS: After lenvatinib administration, a change rate in the NO from 0.27 to 4.16 was observed. There was no difference between the clinical response to lenvatinib and the change rate of NO (p = 0.632). However, the change rate of NO was significantly lower in patients with AEs than in those without AEs (p = 0.030). When a reduction in NO rate of < 0.8 was defined as a clinically significant reduction of NO (CSRN), the CSRN group had significantly worse progression-free survival (PFS) and overall survival (OS) than the non-CSRN group (p = 0.029 and p = 0.005, respectively). CONCLUSION: Decreased NO levels were associated with the occurrence of AEs and worse prognosis after lenvatinib administration. Change rate in serum NO can be used as predictive markers in patients receiving lenvatinib therapy for HCC.


Asunto(s)
Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Quinolinas , Antineoplásicos/efectos adversos , Carcinoma Hepatocelular/patología , Humanos , Neoplasias Hepáticas/patología , Óxido Nítrico , Dióxido de Nitrógeno/uso terapéutico , Compuestos de Fenilurea/efectos adversos , Quinolinas/efectos adversos
11.
Anaerobe ; 73: 102502, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34896553

RESUMEN

Recurrent Clostridioides difficile infection (rCDI) is a frustrating condition that may affect a person's quality of life for months. Microbiome-based therapy such as fecal microbiota transplantation (FMT) has been effective for the treatment of rCDI by correcting the imbalance of the gut microbiota. Appropriate antibiotic treatment is recommended for at least two recurrences before offering FMT. Here, we report the case of a 92-year-old woman who experienced five recurrences of Clostridioides difficile infection (CDI) (six episodes in total) complicated by dementia and delirium, both of which were dramatically improved by FMT, which was associated with alterations in fecal microbiota and the metabolome. Analyses of whole microbial communities and metabolomic analyses were performed on stool specimens collected from the patient on the first episode, the third episode, the day of FMT (before FMT), and 2, 8, and 23 weeks after the FMT and from the donor. The patient had various fecal dysbioses on the first and third episodes and on the day of FMT. Two weeks after FMT, diversity of the gut bacteriome as well as the virome increased dramatically and was reflected in a positive clinical outcome for this patient. Metabolomic analysis revealed that short-chain fatty acids, which have been reported to be associated with improved memory function, were increased after FMT.


Asunto(s)
Clostridioides difficile , Infecciones por Clostridium , Delirio , Microbiota , Anciano de 80 o más Años , Infecciones por Clostridium/tratamiento farmacológico , Trasplante de Microbiota Fecal , Femenino , Humanos , Metaboloma , Calidad de Vida , Recurrencia , Resultado del Tratamiento
12.
J Nat Prod ; 83(11): 3223-3229, 2020 11 25.
Artículo en Inglés | MEDLINE | ID: mdl-33074672

RESUMEN

Raman microspectroscopy is a minimally invasive technique that can identify molecules without labeling. In this study, we demonstrate the detection of penicillin G inside Penicillium chrysogenum KF425 fungal cells. Raman spectra acquired from the fungal cells had highly overlapped spectroscopic signatures and hence were analyzed with multivariate curve resolution by alternating least-squares (MCR-ALS) to extract the spectra of individual molecular constituents. In addition to detecting spatial distribution of multiple constituents such as proteins and lipids inside the fungal body, we could also observe the subcellular localization of penicillin G. This methodology has the potential to be employed in screening the production of bioactive compounds by microorganisms.


Asunto(s)
Penicilina G/metabolismo , Penicillium chrysogenum/metabolismo , Espectrometría Raman/métodos , Cromatografía Líquida de Alta Presión/métodos , Fermentación , Análisis de los Mínimos Cuadrados , Análisis Multivariante
13.
Anaerobe ; 66: 102281, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33059044

RESUMEN

Clostridium argentinense produces botulinum neurotoxin type G (BoNT/G). We sequenced and analyzed the plasmid harboring the bont/G gene, designated pCAG, in C. argentinense strain 2740. The pCAG consisted of 140,070 bp containing the bont/G gene cluster. Although this gene cluster showed high similarities in its DNA sequence and ORF arrangement to those of other bont gene clusters, the other regions of the plasmid did not. A phylogenetic study suggested that pCAG had a unique evolutionary history compared with other clostridial bont-harboring plasmids. This suggests that pCAG is possibly a novel type of plasmid expressing the bont/G gene in C. argentinense.


Asunto(s)
Toxinas Botulínicas/genética , Clostridium/genética , Infecciones por Clostridium/microbiología , ADN Bacteriano , Evolución Molecular , Familia de Multigenes , Filogenia , Plásmidos , ARN Ribosómico 16S , Análisis de Secuencia
15.
Int J Syst Evol Microbiol ; 70(5): 3069-3075, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32223833

RESUMEN

A novel marine actinomycete, designated strain KJ-029T, was isolated from a marine sediment sample (water depth of 226 m) in Kagoshima, Japan. 16S rRNA gene sequence analysis revealed that the new isolate was most closely related to Micromonospora craniellae LHW 63014T (99.3 % similarity). Phylogenetic analyses of the genus Micromonospora based on 16S rRNA gene sequences showed that strain KJ-029T was clustered with Micromonospora craniellae LHW 63014T and Micromonospora endophytica 202201T. However, digital DNA-DNA hybridization analyses presented low levels of relatedness in the range of 24.8-32.9 % between strain KJ-029T and the above closely related strains. The novel strain contained meso-diaminopimelic acid and 3-OH-diaminopimelic acid, d-glutamic acid, glycine and d-alanine in the cell-wall peptidoglycan. The acyl type of the peptidoglycan was glycolyl and mycolic acids were absent. The major menaquinone was MK-9(H4). The whole-cell sugars consisted of glucose, mannose, xylose and ribose. Phosphatidylethanolamine was detected as the major phospholipid and corresponded to phospholipid type II. The predominant cellular fatty acid was iso-C16 : 0. The DNA G+C content of the genomic DNA was 71.5 mol%. Based on the present polyphasic study, strain KJ-029T represents a novel species of the genus Micromonospora, for which the name Micromonospora pelagivivens sp. nov. is proposed. The type strain is KJ-029T (=NBRC 113519T=TBRC 9233T).


Asunto(s)
Sedimentos Geológicos/microbiología , Micromonospora/clasificación , Filogenia , Técnicas de Tipificación Bacteriana , Composición de Base , Pared Celular/química , ADN Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Grasos/química , Japón , Micromonospora/aislamiento & purificación , Hibridación de Ácido Nucleico , Peptidoglicano/química , Fosfolípidos/química , ARN Ribosómico 16S/genética , Agua de Mar/microbiología , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados
16.
Microorganisms ; 8(4)2020 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-32218319

RESUMEN

A novel endophytic actinomycete strain GKU 173T isolated from the roots of Acacia mangium Willd. showed potential plant growth promoting (PGP) activity. Phylogenetic analysis, based on 16S rRNA gene, indicated that strain GKU 173T was the most closely related to Fodinicola feengrottensis HKI 0501T-the only species in the genus Fodinicola. Morphology and chemotaxonomy of strain GKU 173T indicated that it belongs to the genus Fodinicola by having meso-diaminopimelic acid in the cell wall and xylose as the characteristic cell-wall sugars. The cellular fatty acid profile mainly comprised iso-C16:0, anteiso-C17:0, iso-C18:0, and iso-C17:0. The major menaquinones were MK-9(H4), MK-9(H6), and MK-9(H8). The main polar phospholipids contained diphosphatidylglycerol (DPG), phosphatidylethanolamine (PE), and phosphatidylinositol (PI). Genome analysis signified DNA G+C content of 67.81 mol%. The level of digital DNA-DNA relatedness between strain GKU 173T and the type strain was 21.30%. On the basis of polyphasic characteristics, strain GKU 173T clearly represents a novel species of the genus Fodinicola, for which the name Fodinicola acaciae sp. nov. (= TBRC 10620T = NBRC 114213T) is proposed. Furthermore, genome analysis of both strains suggested that members of the genus Fodinicola are promising sources of beneficial PGP-actinomycetes and novel secondary metabolites.

17.
Org Lett ; 21(7): 2180-2184, 2019 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-30859827

RESUMEN

Kozupeptins A and B, novel antimalarial lipopeptides, were isolated from the culture broths of Paracamarosporium sp. FKI-7019. They exhibited potent antimalarial activity against chloroquine-sensitive and -resistant Plasmodium falciparum strains in vitro. The structural elucidation was accomplished by a combination of spectroscopic analyses and chemical approaches including a total synthesis of kozupeptin A. Synthetic kozupeptin A demonstrated a therapeutic effect in vivo, and an intermediate exhibited much higher antimalarial activity than kozupeptin A.


Asunto(s)
Antimaláricos/síntesis química , Antimaláricos/farmacología , Cloroquina/farmacología , Plasmodium falciparum/efectos de los fármacos , Animales , Antimaláricos/química , Cloroquina/química , Estructura Molecular , Plasmodium falciparum/química
18.
Int J Syst Evol Microbiol ; 69(5): 1299-1305, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30789325

RESUMEN

A novel actinomycete, designated as strain H219T, was isolated from rhizosphere soil collected under an Elephant ear plant (Colocasiaesculenta) in Bangkok, Thailand. Strain H219T was characterised using a polyphasic approach. Phylogenetic analysis of the 16S rRNA gene sequences revealed that this isolate was most closely related to Saccharopolyspora tripterygii JCM 32123T (97.6 %), Saccharopolyspora dendranthemae NBRC 108675T (97.5 %) and Saccharopolyspora flava NBRC 16345T (97.5 %). However, DNA-DNA hybridization analyses showed a low relatedness in the range of 39-48 % between the novel isolate and the above closely related strains. The cell-wall peptidoglycan of strain H219T contained meso-diaminopimelic acid. The diagnostic whole-cell sugars consisted of arabinose and galactose. The cellular fatty acid profile mainly comprised iso-C16 : 0, anteiso-C17 : 0, iso-C15 : 0, and 10-methyl C17 : 0. The major menaquinone was MK-9(H4). The detected phospholipids were diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylethanolamine-containing hydroxylated fatty acids and an unknown phospholipid. The DNA G+C content was 70.6 mol%. Strain H219T represented chemotaxonomic and morphological characteristics that were consistent with members of the genus Saccharopolyspora. However, strain H219T could be distinguished from closely related strains by several phenotypic properties. Based on the data from the polyphasic studies, we propose that strain H219T is a novel species within the genus Saccharopolyspora, Saccharopolysporarhizosphaerae sp. nov. The type strain is H219T (=TBRC 8564T=NBRC 113388T).


Asunto(s)
Colocasia/microbiología , Filogenia , Rizosfera , Saccharopolyspora/clasificación , Microbiología del Suelo , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Grasos/química , Hibridación de Ácido Nucleico , Peptidoglicano/química , Fosfolípidos/química , ARN Ribosómico 16S/genética , Saccharopolyspora/aislamiento & purificación , Análisis de Secuencia de ADN , Tailandia , Vitamina K 2/análogos & derivados , Vitamina K 2/química
19.
J Biosci Bioeng ; 127(5): 549-553, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30503170

RESUMEN

Two new nanaomycin analogs, nanaomycin I and J, were isolated from a cultured broth of an actinomycete strain, "Streptomyces rosa subsp. notoensis" OS-3966. In our previous study, we have confirmed the occurrence of nanaomycin I (m/z = 482 [M + H]+) that lacks a pseudo-disaccharide from the mycothiol of nanaomycin H under same culture condition. In this study, to confirm the structure of nanaomycin I, the strain "S. rosa subsp. notoensis" OS-3966 was re-cultured and the target compound with m/z = 482 [M + H]+ was isolated. Furthermore, we discovered another new analog, designated as nanaomycin J in isolating nanaomycin I. The NMR analyses revealed that the structures of nanaomycin I and J are N-acetylcysteine S-conjugates without a pseudo-disaccharide and N-acetylcysteine S-conjugates without a myo-inositol of nanaomycin H, respectively. The relative configurations of the tetrahydropyrane moiety of nanaomycin I and J were determined by rotating-frame overhauser effect spectroscopy (ROESY) analysis. Absolute configurations of the N-acetylcysteine moiety of nanaomycin I and J were determined by advanced Marfey's analyses for acid hydrolysis of de-sulfurized nanaomycin I and J with Raney nickel. Nanaomycin I and J showed moderate cytotoxicity against several human tumor cell lines.


Asunto(s)
Antiinfecciosos/metabolismo , Cisteína/metabolismo , Glicopéptidos/metabolismo , Inositol/metabolismo , Streptomyces/metabolismo , Antiinfecciosos/química , Supervivencia Celular/efectos de los fármacos , Cisteína/química , Glicopéptidos/química , Humanos , Inositol/química , Estructura Molecular , Streptomyces/química
20.
J Antibiot (Tokyo) ; 71(8): 749-752, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29679043

RESUMEN

Actinoallolides are anti-trypanosomal macrolides isolated from the secondary metabolites of two endophytic actinomycete strains, Actinoallomurus fulvus MK10-036 and K09-0307. A putative actinoallolide biosynthetic gene cluster was predicted from the genome sequence of the strain K09-0307. The gene cluster spans a contiguous 53 kb DNA region that comprises seven genes encoding three PKSs (aalA1, aalA2, and aalA3), cytochrome P450 (aalB), acyl-CoA dehydrogenase (aalC), crotonyl-CoA reductase (aalD), and TetR family regulator (aalR). The entire gene cluster was cloned into a plasmid pYIK1 by assembling DNA fragments, which were obtained from two cosmids containing left and right parts of the gene cluster. Following the introduction of an ermE* promoter at 100bp upstream from the start codon of aalA1, the gene cluster was introduced into Streptomyces coelicolor M1152. Subsequent LC-MS analysis revealed production of actinoallolide A in the culture broth. Thus, the actinoallolide biosynthetic gene cluster was identified by heterologous expression in Streptomyces.


Asunto(s)
Macrólidos/metabolismo , Macrólidos/farmacología , Complejos Multienzimáticos/genética , Tripanocidas/farmacología , Trypanosoma brucei brucei/efectos de los fármacos , Trypanosoma cruzi/efectos de los fármacos , Tripanosomiasis/tratamiento farmacológico , Actinobacteria/genética , Actinobacteria/metabolismo , Clonación Molecular , Genes Bacterianos/genética , Familia de Multigenes/genética , Enfermedades Desatendidas/tratamiento farmacológico , Enfermedades Desatendidas/parasitología , Plásmidos/genética , Streptomyces coelicolor/genética , Streptomyces coelicolor/metabolismo , Tripanocidas/metabolismo
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