RESUMEN
From the metagenome of a carbamazepine amended selective enrichment culture the genome of a new to science bacterial species affiliating with the genus Nocardioides was reconstructed. From the same enrichment an aerobic actinobacterium, strain CBZ_1T, sharing 99.4% whole-genome sequence similarity with the reconstructed Nocardioides sp. bin genome was isolated. On the basis of 16S rRNA gene sequence similarity the novel isolate affiliated to the genus Nocardioides, with the closest relatives Nocardioides kongjuensis DSM19082T (98.4%), Nocardioides daeguensis JCM17460T (98.4%) and Nocardioides nitrophenolicus DSM15529T (98.2%). Using a polyphasic approach it was confirmed that the isolate CBZ_1T represents a new phyletic lineage within the genus Nocardioides. According to metagenomic, metatranscriptomic studies and metabolic analyses strain CZB_1T was abundant in both carbamazepine and ibuprofen enrichments, and harbors biodegradative genes involved in the biodegradation of pharmaceutical compounds. Biodegradation studies supported that the new species was capable of ibuprofen biodegradation. After 7 weeks of incubation, in mineral salts solution supplemented with glucose (3 g l-1) as co-substrate, 70% of ibuprofen was eliminated by strain CBZ_1T at an initial conc. of 1.5 mg l-1. The phylogenetic, phenotypic and chemotaxonomic data supported the classification of strain CBZ_1T to the genus Nocardioides, for which the name Nocardioides carbamazepini sp. nov. (CBZ_1T = NCAIM B.0.2663 = LMG 32395) is proposed. To the best of our knowledge, this is the first study that reports simultaneous genome reconstruction of a new to science bacterial species using metagenome binning and at the same time the isolation of the same novel bacterial species.
Asunto(s)
Actinomycetales , Nocardioides , Técnicas de Tipificación Bacteriana , Composición de Base , Biopelículas , Carbamazepina , ADN Bacteriano/genética , Ácidos Grasos/análisis , Ibuprofeno , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Microbiología del Suelo , Vitamina K 2/químicaRESUMEN
Chlamydia trachomatis, an obligate intracellular bacterium with limited metabolic capabilities, possesses the futalosine pathway for menaquinone biosynthesis. Futalosine pathway enzymes have promise as narrow-spectrum antibiotic targets, but the activity and essentiality of chlamydial menaquinone biosynthesis have yet to be established. In this work, menaquinone-7 (MK-7) was identified as a C. trachomatis-produced quinone through liquid chromatography-tandem mass spectrometry. An immunofluorescence-based assay revealed that treatment of C. trachomatis-infected HeLa cells with the futalosine pathway inhibitor docosahexaenoic acid (DHA) reduced inclusion number, inclusion size, and infectious progeny. Supplementation with MK-7 nanoparticles rescued the effect of DHA on inclusion number, indicating that the futalosine pathway is a target of DHA in this system. These results open the door for menaquinone biosynthesis inhibitors to be pursued in antichlamydial development.
Asunto(s)
Vías Biosintéticas , Infecciones por Chlamydia/patología , Chlamydia trachomatis/fisiología , Nucleósidos/biosíntesis , Vitamina K 2/análogos & derivados , Antibacterianos/química , Antibacterianos/farmacología , Automatización , Vías Biosintéticas/efectos de los fármacos , Infecciones por Chlamydia/microbiología , Ácidos Docosahexaenoicos/farmacología , Células HeLa , Humanos , Cuerpos de Inclusión/efectos de los fármacos , Cuerpos de Inclusión/metabolismo , Nanopartículas/química , Nucleósidos/química , Vitamina K 2/química , Vitamina K 2/metabolismoRESUMEN
A Gram-stain-negative, non-motile, non-spore-forming, aerobic, rod-shaped and yellow-pigmented bacterium, designated strain Gsoil 183T, was isolated from ginseng-cultivation soil sampled in Pocheon Province, Republic of Korea. This bacterium was characterized to determine its taxonomic position by using a polyphasic approach. Strain Gsoil 183T grew at 10-37 °C and at pH 5.0-9.0 on tryptic soy agar. Strain Gsoil 183T had ß-glucosidase activity, which was responsible for its ability to convert ginsenoside Rb1 (one of the dominant active components of ginseng) to F2. Based on 16S rRNA gene sequencing, strain Gsoil 183T clustered with species of the genus Chryseobacterium and appeared to be closely related to Chryseobacterium sediminis LMG 28695T (99.1â% sequence similarity), Chryseobacterium lactis NCTC 11390T (98.6%), Chryseobacterium rhizoplanae LMG 28481T (98.6%), Chryseobacterium oncorhynchi CCUG 60105T (98.5%), Chryseobacterium viscerum CCUG 60103T (98.4%) and Chryseobacterium joostei DSM 16927T (98.3%). Menaquinone MK-6 was the predominant respiratory quinone and the major fatty acids were iso-C15â:â0, iso-C17â:â0-3OH and summed feature 3 (C16â:â1 ω6c and/or C16â:â1 ω7c). The polar lipids were phosphatidylethanolamine, six unidentified glycolipids, five unidentified aminolipids and three unidentified lipids. The G+C content of the genomic DNA was 36.6 mol%. Digital DNA-DNA hybridization between strain Gsoil 183T and the type strains of C. sediminis, C. lactis, C. rhizoplanae, C. oncorhynchi, C. viscerum and C. joostei resulted in values below 70â%. Strain Gsoil 183T could be differentiated genotypically and phenotypically from the recognized species of the genus Chryseobacterium. The isolate therefore represents a novel species, for which the name Chryseobacterium panacisoli sp. nov. is proposed, with the type strain Gsoil 183T (=KACC 15033T=LMG 23397T).
Asunto(s)
Chryseobacterium , Ginsenósidos , Panax , Filogenia , Microbiología del Suelo , Técnicas de Tipificación Bacteriana , Composición de Base , Chryseobacterium/clasificación , Chryseobacterium/aislamiento & purificación , ADN Bacteriano/genética , Ácidos Grasos/química , Ginsenósidos/metabolismo , Glucolípidos/química , Hibridación de Ácido Nucleico , Panax/microbiología , Fosfolípidos/química , Pigmentación , ARN Ribosómico 16S/genética , República de Corea , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMEN
Strain EAR8T is a root endophyte isolated from Arthrocnemum macrostachyum plants collected from the Odiel marshes, Huelva (Spain). It presented in vitro plant growth-promoting properties and improved the plant growth and heavy metal accumulation in polluted soils playing an important role in phytoremediation strategies. Phenotypically, strain EAR8T cells were Gram-positive, aerobic and non-motile rods with terminal oval endospores and non-swollen sporangia which form beige, opaque, butyrous, raised and irregular colonies with undulate margins. The strain was able to grow between 15-45 °C, at pH 6.0-9.0 and tolerated 0-25â% NaCl (w/v) showing optimal growth conditions on trypticase soy agar plates supplemented with 2.5â% NaCl (w/v) at pH 7.0 and 37 °C for 24 h. Chemotaxonomic analyses showed that the isolate has meso-diaminopimelic acid as the peptidoglycan in the cell wall and MK-7 as the major respiratory quinone. The predominant fatty acids were anteiso-C15â:â0 and iso-C15â:â0 and the polar lipid profile was composed of diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. Phylogenetic analyses based on the whole proteomes of closest sequenced relatives confirmed that strain EAR8T is affiliated to the genus Rossellomorea and forms a clade with Rossellomorea vietnamensis 15-1T with maximum support. Genome analyses showed that EAR8T has indole-3-acetic acid and siderophore biosynthesis and transporters genes and genes related to resistance against heavy metals. Phenotypic and phylogenomic comparative studies suggested that strain EAR8T is a new representative of the genus Rossellomorea and the name Rossellomorea arthrocnemi sp. nov. is proposed. Type strain is EAR8T (=CECT 9072T=DSM 103900T).
Asunto(s)
Bacillaceae/clasificación , Chenopodiaceae/microbiología , Metales Pesados , Filogenia , Microbiología del Suelo , Contaminantes del Suelo , Bacillaceae/aislamiento & purificación , Técnicas de Tipificación Bacteriana , Composición de Base , Biodegradación Ambiental , ADN Bacteriano/genética , Ácido Diaminopimélico/química , Endófitos/clasificación , Endófitos/aislamiento & purificación , Ácidos Grasos/química , Peptidoglicano/química , Fosfolípidos/química , Raíces de Plantas/microbiología , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , España , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMEN
Osteoporosis (OP) and vascular calcification (VC) represent relevant health problems that frequently coexist in the elderly population. Traditionally, they have been considered independent processes, and mainly age-related. However, an increasing number of studies have reported their possible direct correlation, commonly defined as "bone-vascular crosstalk". Vitamin K2 (VitK2), a family of several natural isoforms also known as menaquinones (MK), has recently received particular attention for its role in maintaining calcium homeostasis. In particular, VitK2 deficiency seems to be responsible of the so-called "calcium paradox" phenomenon, characterized by low calcium deposition in the bone and its accumulation in the vessel wall. Since these events may have important clinical consequences, and the role of VitK2 in bone-vascular crosstalk has only partially been explained, this review focuses on its effects on the bone and vascular system by providing a more recent literature update. Overall, the findings reported here propose the VitK2 family as natural bioactive molecules that could be able to play an important role in the prevention of bone loss and vascular calcification, thus encouraging further in-depth studies to achieve its use as a dietary food supplement.
Asunto(s)
Vasos Sanguíneos/efectos de los fármacos , Resorción Ósea/patología , Huesos/irrigación sanguínea , Calcificación Vascular/patología , Vitamina K 2/farmacología , Animales , Huesos/efectos de los fármacos , Suplementos Dietéticos , Humanos , Vitamina K 2/químicaRESUMEN
The present study aimed to investigate the physical and turbidimetric properties of cholecalciferol- and menaquinone-loaded lipid nanocarriers emulsified with different ratios of polysorbate 80 and soy lecithin. The lipid nanocarriers were subjected to three different heat treatments, LTLT (low temperature long time), HTST (high temperature short time), and autoclave treatments. Both cholecalciferol and menaquinone were successfully encapsulated in lipid nanocarriers and there was little loss of them during preparation. The droplet size of lipid nanocarriers emulsified with only polysorbate 80 increased and its PDI became larger than 0.3 after autoclave treatment. Moreover, 30.9% and 49.4% of cholecalciferol and menaquinone, respectively, were lost. In turbidimetric analysis, the destabilization by creaming formation in the upper layer of the lipid nanocarriers emulsified with a high polysorbate ratio was observed. However, the use of combination of both emulsifiers inhibited destabilization by flocculation as well as retained the cholecalciferol and menaquinone after all heat treatments.
Asunto(s)
Colecalciferol/química , Lecitinas/química , Lípidos/química , Polisorbatos/química , Vitamina K 2/química , EmulsionesRESUMEN
A novel actinomycete, designated strain QMT-28T, was isolated from rhizosphere soil of Fagopyrum dibotrys collected from Shuangfeng, Hunan Province, PR China. Strain QMT-28T grew well on International Streptomyces Project series media and formed well-developed, branched substrate hyphae and aerial mycelium that differentiated into loose spiral spore chains consisting of cylindrical spores with smooth surfaces. The diagnostic diamino acid was ll-diaminopimelic acid and the whole-cell sugars were galactose and glucose. The predominant fatty acids were C18â:â1 cis9, summed feature 6 (C18â:â2 cis 9,12/C18â:â0 a) and C16â:â0. The polar lipids included diphosphatidylglycerol, hydroxy phospatidylethanolamine, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannosides, phospholipids of unknown structure containing glucosamine and several unidentified phospholipids. The major menaquinones were MK-9, MK-9(H2), MK-9(H4), MK-9(H6) and MK-9(H8). The genome size of strain QMT-28T was about 8.7 Mbp with a G+C content of 71.2 mol%. Phylogenetic analysis showed that the novel strain was closely related to Streptomyces olivochromogenes DSM 40451T (99.5â% similarity), Streptomyces mirabilis NBRC 13450T (98.9â%), Streptomyces kanamyceticus NBRC 13414T (98.9â%), Streptomyces kaempferi I37T (98.9â%) and Streptomyces arcticus ZLN234T (98.8â%). However, the average nucleotide identity values, the digital DNA-DNA hybridization values and the multilocus sequence analysis evolutionary distances between this strain and closely related strains showed that it belonged to a distinct species. In addition, these results were also supported by differences in the phenotypic characteristics between QMT-28T and five closely related type strains. Consequently, strain QMT-28T should represent a novel species of the genus Streptomyces, with the suggested name Streptomyces fagopyri sp. nov. The type strain is QMT-28T (=CICC 24808T=JCM 33796T).
Asunto(s)
Fagopyrum/microbiología , Filogenia , Microbiología del Suelo , Streptomyces/clasificación , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácidos Grasos/química , Tamaño del Genoma , Hibridación de Ácido Nucleico , Fosfolípidos/química , ARN Ribosómico 16S/genética , Rizosfera , Análisis de Secuencia de ADN , Streptomyces/aislamiento & purificación , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMEN
An endophytic actinobacterium, strain CLES2T, was discovered from the surface-sterilized stem of a Thai medicinal plant, Clausena excavala Burm. f., collected from the Phujong-Nayoa National Park, Ubon Ratchathani Province, Thailand. The results of a polyphasic taxonomic study identified this strain as a member of the genus Microbispora and a Gram-stain-positive, aerobic actinobacterium. It had well-developed substrate mycelia, which were non-motile and possessed paired spores. A phylogenetic evaluation based on 16S rRNA gene sequence analysis placed this strain in the family Streptosporangiaceae, being most closely related to Microbispora bryophytorum NEAU-TX2-2T (99.4â%), Microbispora camponoti 2C-HV3T (99.2â%), Microbispora catharanthi CR1-09T (99.2â%) and Microbispora amethystogenes JCM 3021T and Microbispora fusca NEAU-HEGS1-5T (both at 99.1â%). The major cellular fatty acid of this strain was iso-C16â:â0 and major menaquinone was MK-9(H4). The polar lipid profile of strain CLES2T contained diphosphatidylglycerol, phosphatidylmethylethanolamine, phosphatidylinositol and phosphatidylinositol dimannosides. These chemotaxonomic data confirmed the affiliation of strain CLES2T to the genus Microbispora. The DNA G+C content of this strain was 70 mol%. Digital DNA-DNA hybridization and average nucleotide identity blast values between strain CLES2T and M. catharanthi CR1-09T were 62.4 and 94.0â%, respectively. The results of the polyphasic study allowed the genotypic and phenotypic differentiation of strain CLES2T from its closest species with valid names. The name proposed for the new species is Microbispora clausenae sp. nov. The type strain is CLES2T (=DSM 101759T=NRRL B-65340T).
Asunto(s)
Actinobacteria/clasificación , Clausena/microbiología , Filogenia , Actinobacteria/aislamiento & purificación , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Hibridación de Ácido Nucleico , Fosfolípidos/química , Tallos de la Planta/microbiología , Plantas Medicinales/microbiología , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Tailandia , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMEN
An anaerobic and aerotolerant bacterium, strain M12T, was isolated from the meibum of inflamed human meibomian glands. Cells of the strain was Gram-stain-positive, non-spore-forming and non-motile rods. Growth on trypticase soy agar plates supplemented with 5â% sheep blood was fastest at 30-37 °C under anaerobic conditions. The 16S rRNA gene sequence of the strain revealed that it belongs to the genus Cutibacterium with a 98.0â% similarity value to the closest species, Cutibacterium acnes. Genome analysis of the strain with type strains of the other Cutibacterium species resulted in digital DNA-DNA hybridization values of 32.3-22.3% and average nucleotide identity (OrthoANI) values of 86.7-73.6â%. Biochemical and physiological analyses using API rapid ID 32A and API Coryne kits revealed relatively low reactivity of the strain compared with C. acnes and Cutibacterium namnetense. The most abundant major cellular fatty acid was iso-C15â:â0. Fermentation end-products from glucose were propionate, lactate, succinate and acetate. The diagnostic diamino acid of the peptidoglycan was meso-diaminopimelic acid. Major menaquinones were MK-9(H4), MK-9(H2) and MK-9. The major peaks of the MALDI-TOF mass spectrometry spectrum were at 3493, 3712, 6986 and 7424 Da. The DNA G+C content was 59.9 mol%. Based on these findings, we propose a novel species, Cutibacterium modestum. The type strain of C. modestum is M12T (=JCM 33380T=DSM 109769T). On the basis of further genomic analysis, we also provide emended descriptions of Cutibacterium granulosum (Prévot 1938) Scholz and Kilian 2016 and Cutibacterium namnetense (Aubin et al. 2016) Nouioui et al. 2018.
Asunto(s)
Glándulas Tarsales/microbiología , Filogenia , Propionibacteriaceae/clasificación , Lágrimas/microbiología , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Grasos/química , Humanos , Japón , Hibridación de Ácido Nucleico , Peptidoglicano/química , Propionibacteriaceae/aislamiento & purificación , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMEN
A novel bacterial strain, S40T, with strong antifungal activity was isolated from the rhizosphere of green potato collected from Zealand, Denmark. Polyphasic analysis with a combined phenotypic, phylogenetic and genomic approach was used to characterize S40T. Phylogenetic analysis based on the 16S rRNA gene and MLSA (concatenated gyrB, rpoD, infB and atpD sequences) showed that strain S40T was affiliated with the genus Serratia and with Serratia plymuthica PRI-2C as the closest related strain [average nucleotide identity (ANI), 99.26â%; DNA-DNA hybridization (dDDH), 99.20%]. However, whole genome sequence analyses revealed that S40T and S. plymuthica PRI-2C genomes displayed lower similarities when compared to all other S. plymuthica strains (ANI ≤94.34â%; dDDH ≤57.6â% relatedness). The DNA G+C content of strain S40T was determined to be 55.9 mol%. Cells of the strain were Gram-negative, rod-shaped, facultative anaerobic and displayed growth at 10-37 °C (optimum, 25-30 °C) and at pH 6-9 (optimum, pH 6-7). Major fatty acids were C16â:â0 (27.9â%), summed feature (C16â:â1 ω6c/C16â:â1 ω7c; 18.0â%) and C17â:â0 cyclo (15.1â%). The respiratory quinone was determined to be Q8 (94â%) and MK8 (95â%) and the major polar lipids were phosphatidylethanolamine and phosphatidylglycerol. The results of phenotypic, phylogenetic and genomic analyses support the hypothesis that strain S40T represents a novel species of the genus Serratia, for which the name Serratia inhibens sp. nov. is proposed. The type strain is S40T (=LMG 31467T=NCIMB 15235T). In addition, we propose that S. plymuthica PRI-2C is reclassified and transferred to the species S. inhibens as S. inhibens PRI-2C.
Asunto(s)
Antibiosis , Filogenia , Serratia/clasificación , Solanum tuberosum/microbiología , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Dinamarca , Ácidos Grasos/química , Genes Bacterianos , Hibridación de Ácido Nucleico , Fosfolípidos/química , ARN Ribosómico 16S/genética , Rizosfera , Análisis de Secuencia de ADN , Serratia/aislamiento & purificación , Ubiquinona/química , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMEN
Two novel Gram-stain-positive, irregular rod-shaped bacterial strains, dk3136T and dk3543, were isolated from the faeces of Tibetan gazelle (Procapra picticaudata) in the Qinghai-Tibet Plateau of PR China. The cells were aerobic, oxidase-negative and catalase-positive. Colonies were yellowish, circular without any observable aerial mycelium after culturing at 28 â for 3 days on brain-heart infusion (BHI) agar with 5â% sheep blood. The cells grew optimally at 28 °C, pH 7.5 and with 1â% (w/v) NaCl on BHI agar supplemented with 5â% sheep blood. Phylogenetic analysis of the 16S rRNA gene sequences revealed that their nearest phylogenetic relative was Nocardioides solisilvae Ka25T (97.9â% similarity). The results of 16S rRNA gene sequence and phylogenetic/phylogenomic analyses illustrated that N. solisilvae Ka25T, Nocardioides gilvus XZ17T, Nocardioides houyundeii 78T and Nocardioides daphniae D287T were their nearest phylogenetic neighbours. The DNA G+C contents of strains dk3136T and dk3543 were 70.3 mol% and 70.4 mol%, respectively. Their genomes exhibit lower than threshold (95-96â%) average nucleotide identity to known species of the genus Nocardioides. ll-2,6-diaminopimelic acid was the diagnostic diamino acid and MK-8(H4) was the predominant respiratory quinone. The major polar lipids were diphosphatidylglycerol and phosphatidylglycerol. The two strains had C18â:â1 ω9c, iso-C16â:â0 and C17â:â1 ω8c as the major fatty acids, and rhamnose and galactose as the main whole-cell sugars. On the basis of the results of our genotypic, phenotypic and biochemical analyses, we conclude that strains dk3136T and dk3543 represent a novel species in genus Nocardioides, for which the name Nocardioides jishulii sp. nov. is proposed. The type strain is dk3136T (=CGMCC 4.7570T=JCM 33496T=KCTC 49314T).
Asunto(s)
Actinobacteria/clasificación , Antílopes/microbiología , Heces/microbiología , Filogenia , Actinobacteria/aislamiento & purificación , Animales , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Peptidoglicano/química , Fosfolípidos/química , Pigmentación , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Tibet , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMEN
A novel archaeal strain designated as SPP-AMP-1T was isolated from saltpan soil, using the serial dilution method on a halophilic archaeal medium supplemented with ampicillin. Cells were both rod-shaped and pleomorphic in nature, non-motile, unable to produce acid from a variety of sugars or grow anaerobically with different substrates (l-arginine) and electron acceptors (DMSO, nitrate). Optimal growth was observed at 42 °C, 3.4-4.2 M NaCl and pH 7.2. Cells did not lyse in distilled water and grew in the absence of Mg2+ ions. Phylogenetic analysis based on the sequences of 16S rRNA gene, amino acid sequence of ß'-subunit of RNA polymerase and 400 conserved proteins retrieved from the whole genome assemblies showed that strain SPP-AMP-1T was distantly related to any existing genera within the family Halobacteriaceae. MK-8 was the only quinone detected. Polar lipid analysis showed a unique combination of diethyl derivatives of phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, glycosyl-mannosyl-glucosyl diether and sulphated glycosyl-mannosyl-glucosyl diether as the major lipids. The G+C content of genomic DNA is 57.7 mol%. The phenotypic, phylogenetic and genomic data supported the concept of the novel genus status of strain SPP-AMP-1T in the family Halobacteriaceae for which the name Halocatena pleomorpha gen. nov., sp. nov., is proposed; the type strain is SPP-AMP-1T (=JCM 31368T=KCTC 4276T=MTCC 12579T).
Asunto(s)
Halobacteriaceae/clasificación , Filogenia , Salinidad , Microbiología del Suelo , Composición de Base , ADN de Archaea/genética , Halobacteriaceae/aislamiento & purificación , India , Lípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Cloruro de Sodio , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMEN
Recently, several studies have indicated that an adequate intake of menaquinone-7 (MK-7) offers numerous health benefits. However, the low availability of MK-7 in the diet necessitates the development of dietary supplements or functional food products to complement natural food sources and meet the daily intake requirements. Like most biological molecules, MK-7 can exist as geometric isomers that can occur in the cis, trans, and cis/trans forms; however, only the all-trans form is biologically significant. MK-7 is traditionally produced through bacterial fermentation, but various synthetic preparations have lately become available. The isomer composition in the final product is influenced by numerous factors, including the methods of production and purification, as well as particular environmental and storage conditions. The MK-7 profile obtained from the various production methods has not yet been elucidated, and the ideal method for the synthesis of the all-trans form of the vitamin is also debatable. Consequently, the quantification of the MK-7 profile of various products is necessary to develop an understanding of the factors that influence the proportion of isomers that are obtained in different preparations. Several possible methods exist for the quantification of MK-7 isomers, and of these, liquid chromatography in conjunction with mass spectrometry techniques appears to be the most promising. Evaluation of the isomer composition is an important consideration, as only the all-trans form sustains biological activity. Furthermore, knowledge of the prominent factors that influence the MK-7 composition may also enable their manipulation to obtain a more favorable MK-7 profile in the final product.
Asunto(s)
Vitamina K 2/análogos & derivados , Vitaminas/química , Vitaminas/metabolismo , Disponibilidad Biológica , Dieta , Suplementos Dietéticos , Fermentación , Humanos , Isomerismo , Vitamina K 2/análisis , Vitamina K 2/síntesis química , Vitamina K 2/química , Vitamina K 2/metabolismo , Vitaminas/análisis , Vitaminas/síntesis químicaRESUMEN
The taxonomic position of a novel actinomycete isolate, designated strain GGCR-6T, isolated from the healthy leaves of Xanthium sibiricum collected from the botanic garden of Hunan University of Science and Technology in Hunan province, PR China, was determined by a polyphasic approach. GGCR-6T grew well on ISP series media and formed well-developed, branched substrate hyphae and aerial mycelium that differentiated into straight spore chains consisting of cylindrical spores with smooth surfaces. The diagnostic diamino acid was ll-diaminopimelic acid. The major menaquinones were MK-9(H8), MK-9(H2), MK-9 and MK-9(H6). The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphotidylinositol and phosphatidylinositol mannosides. The predominant fatty acids were C16â:â1ω9c, iso-C16â:â0 and C16â:â0. The phenotypic characteristics of GGCR-6T indicated that it represented a member of the genus Streptomyces. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that GGCR-6T was most closely related to Streptomyces cyaneus NRRL B2296T and Streptomyces griseoruber NRRL B1818T. However, the digital DNA-DNA hybridization, the average nucleotide identity and the multi locus sequence analysis evolutionary distance clearly separate GGCR-6T from the phylogenetically closely related species. Furthermore, the novel isolate was distinctly differentiated from S. cyaneus NRRL B2296T and S. griseoruber NRRL B1818T by morphological, physiological and biochemical characteristics. Based on these data, strain GGCR-6T should be designated as a representative of a novel species of the genus Streptomyces, for which the name Streptomyces aquilus sp. nov. is proposed. The type strain is strain GGCR-6T (=CICC 11055T=JCM 33584T).
Asunto(s)
Actinobacteria/clasificación , Filogenia , Streptomyces/clasificación , Xanthium/microbiología , Actinobacteria/aislamiento & purificación , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Grasos/química , Hibridación de Ácido Nucleico , Fosfolípidos/química , Hojas de la Planta/microbiología , Plantas Medicinales/microbiología , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Streptomyces/aislamiento & purificación , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMEN
A Gram-stain-negative bacterial strain, designated CA10T, was isolated from bovine raw milk sampled in Anseong, Republic of Korea. Cells were yellow-pigmented, aerobic, non-motile bacilli and grew optimally at 30 °C and pH 7.0 on tryptic soy agar without supplementation of NaCl. Phylogenetic analysis based on the 16S rRNA gene sequences revealed that strain CA10T belonged to the genus Chryseobacterium, family Flavobacteriaceae, and was most closely related to Chryseobacterium indoltheticum ATCC 27950T (98.75â% similarity). The average nucleotide identity and digital DNA-DNA hybridization values of strain CA10T were 94.4 and 56.9â%, respectively, relative to Chryseobacterium scophthalmum DSM 16779T, being lower than the cut-off values of 95-96 and 70â%, respectively. The predominant respiratory quinone was menaquinone-6; major polar lipid, phosphatidylethanolamine; major fatty acids, iso-C15â:â0, summed feature 9 (iso-C17â:â1ω9c and/or C16â:â0 10-methyl), summed feature 3 (iso-C15â:â0 2-OH and/or C16â:â1ω7c) and iso-C17â:â0 3-OH. The results of physiological, chemotaxonomic and biochemical analyses suggested that strain CA10T is a novel species of genus Chryseobacterium, for which the name Chryseobacterium mulctrae sp. nov. is proposed. The type strain is CA10T (=KACC 21234T=JCM 33443T).
Asunto(s)
Chryseobacterium/clasificación , Leche/microbiología , Filogenia , Animales , Técnicas de Tipificación Bacteriana , Composición de Base , Bovinos , Chryseobacterium/aislamiento & purificación , ADN Bacteriano/genética , Ácidos Grasos/química , Femenino , Hibridación de Ácido Nucleico , Fosfatidiletanolaminas/química , ARN Ribosómico 16S/genética , República de Corea , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMEN
Szterk et al. (Food Chemistry 243 (2018) 403-409) have recently analyzed the content of menaquinone-7 (MK-7) in eight dietary supplements. The authors concluded that five out of eight were below the declared content. For all samples, the authors used tetrahydrofuran (THF) to extract MK-7 prior to analysis. Two of the tested products that were below the declared content were microencapsulated MK-7 which had a coating with limited solubility in THF. By dissolving the coating with water and ethanol prior to extraction with ethyl acetate, all MK-7 will be made accessible prior to analysis by HPLC. We have repeated the analysis of the two microencapsulated products that Szterk et al. claimed were below the declared content, and have shown they contain 102% and 105% of the label claim. Since Szterk et al. have used a solvent that does not dissolve the coating on microencapsulated MK-7, their conclusion is not justified and is thus misleading.
Asunto(s)
Suplementos Dietéticos/análisis , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMEN
Menaquinone-7 (MK7) is a member of the vitamin K family in which interest has considerably increased over the last decade, mainly due to its beneficial role in human health. MK7 can be produced by synthesis or fermentation, and its purity profile can differ depending on methodologies and extraction procedures. Finished formulations show a high heterogeneity of purity profiles, as well as frequent discrepancies in the nominal content, compared to the actual title. The present study compared purity profiles of different raw material and related them to their stability in normal (12 months/25 °C/60%RH) and accelerated conditions (6 months/40 °C/75% RH) in order to test their performance in the presence of different common excipients. Results showed higher purity profile results in enhanced stability, and this could explain title discrepancies found in finished products, which are present on the market worldwide.
Asunto(s)
Composición de Medicamentos/métodos , Vitamina K 2/análogos & derivados , Cromatografía Líquida de Alta Presión , Contaminación de Medicamentos , Estabilidad de Medicamentos , Fermentación , Estructura Molecular , Polvos , Vitamina K 2/análisis , Vitamina K 2/síntesis química , Vitamina K 2/químicaRESUMEN
A novel endophytic bacterium, designated strain SZ4R5S7T, was isolated from surface-sterilized root of an endangered medicinal plant (Ferula songorica Pall. ex Spreng) collected from Xinjiang, north-west China. The taxonomic position of the strain was investigated by using a polyphasic approach. The strain was found to be aerobic, Gram-stain-positive, oxidase-negative and catalase-positive, short rods and non-motile. Strain SZ4R5S7T grew at 4-37 °C (optimum, 28 °C), pH 5.0-9.0 (pH 6.0-8.0) and in the presence of 0-4â% (w/v) NaCl. The polar lipids detected for strain SZ4R5S7T were phosphatidylglycerol, diphosphatidylglycerol, phosphatidylinositol and two unidentified lipids. The predominant menaquinone of strain SZ4R5S7T was MK-8(H4), and the major fatty acids were iso-C16â:â0 and anteiso-C14â:â0. The DNA G+C content was determined to be 72.4 mol%. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that strain SZ4R5S7T belongs to the genus Nocardioides and showed highest levels of 16S rRNA gene sequence similarity to members of the strain Nocardioideskribbensis KSL-2T (97.8â%). On the basis of phenotypic, genotypic and phylogenetic data, strain SZ4R5S7T represents a novel species in the genus Nocardioides, for which the name Nocardioides ferulae sp. nov. is proposed and the type strain is SZ4R5S7T (=CGMCC 4.7456T=KCTC 39994T).
Asunto(s)
Actinobacteria/clasificación , Ferula/microbiología , Filogenia , Plantas Medicinales/microbiología , Actinobacteria/aislamiento & purificación , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Especies en Peligro de Extinción , Ácidos Grasos/química , Fosfolípidos/química , Raíces de Plantas/microbiología , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMEN
A novel Gram-positive, non-motile, non-spore-forming and aerobic bacterium, designated strain VA37-3T, was isolated from a marine sediment sample collected at 19.2 m water depth from Valparaíso bay, Chile. Strain VA37-3T exhibits 97.6â% 16S rRNA gene sequence similarity to Corynebacterium marinum D7015T, 96.4â% to Corynebacterium humireducens MFC-5T and 96â% to Corynebacterium testudinoris M935/96/4T; and a rpoB gene sequence similarity of 85.1â% to Corynebacterium pollutisoli VMS11T, both analyses suggesting that strain VA37-3T represents a novel species of Corynebacterium. Physiological testing indicated that strain VA37-3T requires artificial sea water or sodium-supplemented media for growth, representing the first obligate marine actinomycete of the genus Corynebacterium. The genome of the proposed new species, along with the type strains of its most closely related species were sequenced and characterized. In silico genome-based similarity analyses revealed an ANIb of 72.8â% (C. marinum D7015T), ANIm of 85.0â% (Corynebacterium mustelae DSM 45274T), tetra of 0.90 (Corynebacterium callunae DSM 20147T) and ggdc of 24.7â% (Corynebacterium kutscheri DSM 20755T) when compared with the closest related strains. The genomic DNA G+C content of strain VA37-3T was 57.0â%. Chemotaxonomic assessment of strain VN6-2T showed the major fatty acids were C18â:â1ω9c and C16â:â0. Menaquinones predominantly consisted of MK-8(II-H2). Polar lipids consisted of diphosphatidylglycerol, glycolipids, phosphatidylglycerol, phosphoglycolipid and phosphatidylinositol. Mycolic acids also were present. Overall, the results from phylogenetic, phenotypic and genomic analyses confirmed that strain VA37-3T represents a novel species of the genus Corynebacterium, for which the name Corynebacterium alimapuense sp. nov. is proposed, with VA37-3T as the type strain (=CCUG 69366T=NCIMB 15118T).
Asunto(s)
Corynebacterium/clasificación , Sedimentos Geológicos/microbiología , Filogenia , Agua de Mar/microbiología , Técnicas de Tipificación Bacteriana , Composición de Base , Bahías , Chile , Corynebacterium/aislamiento & purificación , ADN Bacteriano/genética , Ácidos Grasos/química , Glucolípidos/química , Hibridación de Ácido Nucleico , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMEN
A Gram-stain-negative, rod-shaped (0.2-0.4 µm×1.2-1.7 µm), endophytic bacterium, designated HBUM179779T, was isolated from the stem of a medicinal plant,Gynura bicolor, collected from Pixian county in Sichuan province, China. The strain did not produce endospores and its cells could secrete mucus. The predominant menaquinone was MK-7. The polar lipids were phosphatidylethanolamine, phosphatidylinositolmannosides, two unknown aminolipids, two unknown glycolipids and an unknown phospholipid. Branched fatty acids (iso-) and hydroxy fatty acids were the main fatty acids, which mainly included iso-C15â:â0, iso-C15â:â1 G and iso-C17â:â0 3-OH. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain HBUM179779T fell within the family Chitinophagaceae, and its closest neighbour was Pseudoflavitalea rhizosphaerae T16R-265T (94.46â%). However, strain HBUM179779T did not make a coherent clade with members of the recognized organisms. The average nucleotide identity value between strain HBUM179779T and Pseudoflavitalea rhizosphaerae T16R-265T was 67.1â%. On the basis of the phylogenetic and phenotypic characteristics of this bacterium, a novel genus and species, Gynurincola endophyticus gen. nov., sp. nov., is proposed. The type strain is HBUM179779T (=CGMCC 1.15525T=NBRC 112424T).