RESUMO
Halophilic archaea of the class Halobacteria are the most salt-requiring prokaryotes within the domain Archaea. In 1997, minimal standards for the description of new taxa in the order Halobacteriales were proposed. From then on, the taxonomy of the class Halobacteria provides an excellent example of how changing concepts on prokaryote taxonomy and the development of new methods were implemented. The last decades have witnessed a rapid expansion of the number of described taxa within the class Halobacteria coinciding with the era of genome sequencing development. The current members of the International Committee on Systematics of Prokaryotes Subcommittee on the Taxonomy of Halobacteria propose these revisions to the recommended minimal standards and encourage the use of advanced technologies in the taxonomic description of members of the Halobacteria. Most previously required and some recommended minimal standards for the description of new taxa in the class Halobacteria were retained in the present revision, but changes have been proposed in line with the new methodologies. In addition to the 16S rRNA gene, the rpoB' gene is an important molecular marker for the identification of members of the Halobacteria. Phylogenomic analysis based on concatenated conserved, single-copy marker genes is required to infer the taxonomic status of new taxa. The overall genome relatedness indexes have proven to be determinative in the classification of the taxa within the class Halobacteria. Average nucleotide identity, digital DNA-DNA hybridization, and average amino acid identity values should be calculated for rigorous comparison among close relatives.
Assuntos
Ácidos Graxos , Halobacteriales , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ácidos Graxos/química , Técnicas de Tipagem Bacteriana/métodos , DNA Bacteriano/genética , Composição de BasesRESUMO
The t-type trichothecene producers Fusarium sporotrichioides and Fusarium graminearum protect themselves against their own mycotoxins by acetylating the C-3 hydroxy group with Tri101p acetylase. To understand the mechanism by which they deal with exogenously added d-type trichothecenes, the Δtri5 mutants expressing all but the first trichothecene pathway enzymes were fed with trichodermol (TDmol), trichothecolone (TCC), 8-deoxytrichothecin, and trichothecin. LC-MS/MS and NMR analyses showed that these C-3 unoxygenated trichothecenes were conjugated with glucose at C-4 by α-glucosidic linkage. As t-type trichothecenes are readily incorporated into the biosynthetic pathway following the C-3 acetylation, the mycotoxins were fed to the ΔFgtri5ΔFgtri101 mutant to examine their fate. LC-MS/MS and NMR analyses demonstrated that the mutant conjugated glucose at C-4 of HT-2 toxin (HT-2) by α-glucosidic linkage, while the ΔFgtri5 mutant metabolized HT-2 to 3-acetyl HT-2 toxin and T-2 toxin. The 4-O-glucosylation of exogenously added t-type trichothecenes appears to be a general response of the ΔFgtri5ΔFgtri101 mutant, as nivalenol and its acetylated derivatives appeared to be conjugated with hexose to some extent. The toxicities of 4-O-glucosides of TDmol, TCC, and HT-2 were much weaker than their corresponding aglycons, suggesting that 4-O-glucosylation serves as a phase II xenobiotic metabolism for t-type trichothecene producers.
Assuntos
Fusarium/metabolismo , Glucose/metabolismo , Desintoxicação Metabólica Fase II , Tricotecenos/metabolismo , Acetilação , Cromatografia Líquida , Espectrometria de Massas em TandemRESUMO
The haloarchaeal genera Natrinema and Haloterrigena were described almost simultaneously by two different research groups and some strains studied separately were described as different species of these genera. Furthermore, the description of additional species were assigned to either Natrinema or Haloterrigena, mainly on the basis of the phylogenetic comparative analysis of single genes (16S rRNA gene and more recently rpoB' gene), but these species were not adequately separated or assigned to the corresponding genus. Some studies suggested that the species of these two genera should be unified into a single genus, while other studies indicated that the genera should remain but some of the species should be reassigned. In this study, we have sequenced or collected the genomes of the type strains of species of Natrinema and Haloterrigena and we have carried out a comparative genomic analysis in order to clarify the controversy related to these two genera. The phylogenomic analysis based on the comparison of 525 translated single-copy orthologous genes and the Overall Genome Relatedness Indexes (i.e., AAI, POCP, ANI, and dDDH) clearly indicate that the species Haloterrigena hispanica, Haloterrigena limicola, Haloterrigena longa, Haloterrigena mahii, Haloterrigena saccharevitans, Haloterrigena thermotolerans, and Halopiger salifodinae should be transferred to the genus Natrinema, as Natrinema hispanicum, Natrinema limicola, Natrinema longum, Natrinema mahii, Natrinema saccharevitans, Natrinema thermotolerans, and Natrinema salifodinae, respectively. On the contrary, the species Haloterrigena turkmenica, Haloterrigena salifodinae, and Haloterrigena salina will remain as the only representative species of the genus Haloterrigena. Besides, the species Haloterrigena daqingensis should be reclassified as a member of the genus Natronorubrum, as Natronorubrum daqingense. At the species level, Haloterrigena jeotgali and Natrinema ejinorense should be considered as a later heterotypic synonyms of the species Haloterrigena (Natrinema) thermotolerans and Haloterrigena (Natrinema) longa, respectively. Synteny analysis and phenotypic features also supported those proposals.
RESUMO
A mannan-degrading halophilic archaeal strain, MD130-1T, was isolated from a commercial salt sample. Cells were motile, rod-shaped, and stained Gram-negative. Colonies were pink pigmented. Strain MD130-1T was able to grow at 1.5-4.6 M NaCl (optimum, 3.6 M) at pH 6.0-8.0 (optimum, pH 7.0) and at 25-50 °C (optimum, 40 °C). The DNA G+C content was 62.1 mol% (genome). The orthologous 16S rRNA gene sequence showed the highest similarity (99.4â%) to those of Haloarcula japonica JCM 7785T and Haloarcula hispanica JCM 8911T. The values of genome relatedness between strain MD130-1T and Haloarcula species were 84.33-85.96â% in ANIb and 30.4-32.9â% using GGDC formula 2. The polar lipids of strain MD130-1T were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and triglycosyl diether-2. Based on the results of phenotypic and phylogenetic analyses, the strain represents a new species of the genus Haloarcula, for which the name Haloarcula mannanilytica sp. nov. is proposed. The type strain is MD130-1T (=JCM 33835T=KCTC 4287T) isolated from commercial salt made in Ishikawa prefecture, Japan.
Assuntos
Haloarcula/classificação , Filogenia , Cloreto de Sódio/análise , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Arqueal/genética , DNA Bacteriano/genética , Ácidos Graxos/química , Galactose/análogos & derivados , Haloarcula/isolamento & purificação , Japão , Mananas/metabolismo , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNARESUMO
Hadal trench bottom (>6000 m below sea level) sediments harbor higher microbial cell abundance compared with adjacent abyssal plain sediments. This is supported by the accumulation of sedimentary organic matter (OM), facilitated by trench topography. However, the distribution of benthic microbes in different trench systems has not been well explored yet. Here, we carried out small subunit ribosomal RNA gene tag sequencing for 92 sediment subsamples of seven abyssal and seven hadal sediment cores collected from three trench regions in the northwest Pacific Ocean: the Japan, Izu-Ogasawara, and Mariana Trenches. Tag-sequencing analyses showed specific distribution patterns of several phyla associated with oxygen and nitrate. The community structure was distinct between abyssal and hadal sediments, following geographic locations and factors represented by sediment depth. Co-occurrence network revealed six potential prokaryotic consortia that covaried across regions. Our results further support that the OM cycle is driven by hadal currents and/or rapid burial shapes microbial community structures at trench bottom sites, in addition to vertical deposition from the surface ocean. Our trans-trench analysis highlights intra- and inter-trench distributions of microbial assemblages and geochemistry in surface seafloor sediments, providing novel insights into ultradeep-sea microbial ecology, one of the last frontiers on our planet.
Assuntos
Bactérias/isolamento & purificação , Sedimentos Geológicos/microbiologia , Microbiota , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , Sedimentos Geológicos/química , Japão , Nitratos/metabolismo , Oceano PacíficoRESUMO
A novel halophilic archaeon, designated strain WIIAL99T, was isolated from Lake Meyghan, a hypersaline lake in Iran. Cells of strain WIIAL99T were non-motile, catalase-positive and oxidase-negative. Strain WIIAL99T required at least 2.5 M NaCl and 0.05 M MgCl2 for growth. Optimal growth was achieved at 3.5 M NaCl and 0.1 M MgCl2. The optimum pH and temperature for growth were pH 7.0 and 37-40 °C; it was able to grow at pH 6.0-8.5 and 20-55 °C. Cells lysed in distilled water and the minimal NaCl concentration to prevent cell lysis was 8â% (w/v). The major polar lipids of strain WIIAL99T were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, disulfated diglycosyl diether and one unidentified glycolipid. The DNA G+C content of strain WIIAL99T was 66.7 mol%. The closest relative was Natronoarchaeum rubrum JCM 17119T with 98.2â% similarity in the orthologous 16S rRNA gene sequence. Analysis of 16S rRNA and rpoB' gene sequences indicated that strain WIIAL99T is a member of the genus Natronoarchaeum in the family Halobacteriaceae and forms a distinct cluster. It was concluded that strain WIIAL99T (=IBRC-M 11062T=LMG 29814T) represents a novel species of the genus Natronoarchaeum, for which the name Natronoarchaeum persicum sp. nov. is proposed.
Assuntos
Halobacteriaceae/classificação , Filogenia , Salinidade , Microbiologia da Água , Composição de Bases , DNA Arqueal/genética , Genes Arqueais , Glicolipídeos/química , Halobacteriaceae/genética , Halobacteriaceae/isolamento & purificação , Irã (Geográfico) , Lagos/microbiologia , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNARESUMO
Two chitin-degrading halophilic archaeal strains, MC-74T and MC-23, were isolated from commercial salt samples. Cells were motile, rod-shaped and stained Gram-negative. Colonies were vermillion-pigmented. Strains MC-74T and MC-23 were able to grow with 1.5-5.1 M NaCl (optimum, 2.6-3.1 M) at pH 6.0-10.0 (optimum, pH 7.0) and at 20-50 °C (optimum, 40 °C). The orthologous 16S rRNA gene sequence similarity between the two strains was 99.8â%, and the closest phylogenetic relative was Salinarchaeum laminariae JCM 17267T with 99.3-99.5â% similarity. The level of DNA-DNA relatedness between the two strains was 93 and 94â% (reciprocally), and those between the two strains and Salinarchaeumlaminariae JCM 17267T were 35-36â% and 38-39â% (reciprocally). The polar lipids of both strains were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and phosphatidylglycerol sulfate. Glycolipids were not detected. Based on the phenotypic and phylogenetic analyses, the strains represent a novel species of the genus Salinarchaeum, for which the name Salinarchaeum chitinilyticum sp. nov. is proposed. The type strain is MC-74T (=JCM 19597T=KCTC 4262T), isolated from solar salt produced in France. Strain MC-23, isolated from a commercial solar salt sample produced in China, is an additional strain of the species.
Assuntos
Halobacteriaceae/classificação , Filogenia , Cloreto de Sódio/análise , China , Quitina/metabolismo , DNA Arqueal/genética , França , Glicolipídeos/química , Halobacteriaceae/genética , Halobacteriaceae/isolamento & purificação , Neisseriaceae/genética , Hibridização de Ácido Nucleico , Fosfatidilgliceróis/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNARESUMO
An extremely halophilic archaeon, designated strain 5-3T, was isolated from a soil sample of Meighan wetland in Iran. Strain 5-3T was strictly aerobic, catalase-positive and oxidase-negative. Cells were Gram-stain-negative, non-motile and ovoid. Colonies of strain 5-3T were cream-coloured. The isolate showed optimum growth at 4.0 M NaCl, 40 °C and pH 7.0. The major polar lipids of the strain were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, two unknown phospholipids and three glycolipids (including one that was chromatographically identical to S2-DGD). The major respiratory quinone was menaquinone MK-8. The G+C content of the genomic DNA was 61.5 mol%. The closest relative was Natrinema salaciae JCM 17869T with 97.3â% similarity in the orthologous 16S rRNA gene sequence. Analysis of 16S rRNA and rpoB' gene sequences indicated that strain 5-3T is a member of the genus Natrinema in the family Natrialbaceae and forms a distinct cluster. On the basis of phylogenetic analysis, and phenotypic and chemotaxonomic characteristics, a novel species of the family Natrialbaceae, Natrinema soli sp. nov., is proposed. The type strain is 5-3T (=IBRC-M 11063T=LMG 29247T).
Assuntos
Halobacteriaceae/classificação , Filogenia , Áreas Alagadas , DNA Arqueal/genética , Genes Arqueais , Glicolipídeos/química , Halobacteriaceae/genética , Halobacteriaceae/isolamento & purificação , Irã (Geográfico) , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Salinidade , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMO
A Gram-stain-negative, rod-pleomorphic, aerobic, halophilic archaeon, strain MK62-1T, was isolated from commercial salt made from seawater in the Philippines. Strain MK62-1T was able to grow at 2.1-4.7 M NaCl (with optimum at 2.1-2.6 M NaCl), pH 6.5-9.5 (optimum, pH 7.0-7.5) and 20-55 °C (optimum, 45-50 °C). Based on the orthologous 16S rRNA gene sequence, the closest relative was Haloparvum sedimenti JCM 30891T with 99.2 % similarity. The RNA polymerase subunit B' gene sequence also showed the highest similarity (97.4 %) to that of Haloparvum sedimenti DYS4T. The DNA G+C content of MK62-1T was 70.1 mol%, while that of Haloparvum sedimenti JCM 30891T was 69.5 mol% by the HPLC method. The levels of DNA-DNA relatedness between MK62-1T and Haloparvum sedimenti JCM 30891T were 60.6 and 60.8 % (reciprocally). The major polar lipids of the isolate were C20C20 archaeol derivatives of phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and phosphatidylglycerol sulfate. Based on the phenotypic and phylogenetic analyses, it is proposed that the isolate represents species within the genus Haloparvum, for which the name Haloparvum alkalitolerans sp. nov. is proposed. The type strain is MK62-1T (=JCM 30442T =KCTC 4214T).
Assuntos
Halobacteriaceae/classificação , Filogenia , Água do Mar/microbiologia , Cloreto de Sódio , Álcalis , Composição de Bases , DNA Arqueal/genética , Genes Arqueais , Halobacteriaceae/genética , Halobacteriaceae/isolamento & purificação , Hibridização de Ácido Nucleico , Filipinas , Fosfolipídeos/química , RNA Polimerase II/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNARESUMO
Three thermo-tolerant halophilic archaeal strains, SR-441T, SR-412 and SR-188, were isolated from commercial salt samples. Cells were non-motile pleomorphic rod-shaped, and stained Gram-negative. Colonies were pink-pigmented. The three strains were able to grow with 1.7-4.6 M NaCl (optimum, 2.5 M), at pH 6.5-9.0 (optimum, pH 8.0) and at 35-60 °C (optimum, 45 °C). The orthologous 16S rRNA gene sequence similarities amongst the three strains were 98.8-99.3 %, and the level of DNA-DNA relatedness was 71-74 and 72-75 % (reciprocally). The closest relative was Halopiger aswanensis JCM 11628T with 98.6 %-99.1 % similarity in the orthologous 16S rRNA gene sequences, followed by two more Halopiger species, Halopiger xanaduensis JCM 14033T (98.5 %-99.1 %) and Halopiger salifodinae JCM 9578T (95.5 %-95.6 %). DNA-DNA relatednesses between the three strains and H. aswanensis JCM 11628T and H. xanaduensis JCM 14033T were 61 and 54 %, respectively. The polar lipids of the three novel strains were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, and bis-sulfated diglycosyl archaeol-1. The most distinctive feature of the three strains was the ability to grow at 60 °C, while the maximum growth temperature of H. aswanensis is 55 °C. Based on phenotypic and phylogenetic analyses, the isolates are considered to represent a novel species of the genus Halopiger, for which the name Halopiger thermotolerans sp. nov. is proposed. The type strain is SR-441T (=JCM 19583T=KCTC 4248T) isolated from solar salt produced in Australia. SR-412 (=JCM 19582) and SR-188 (=JCM 19581) isolated from commercial salt samples are additional strains of the species.
Assuntos
Halobacteriaceae/classificação , Filogenia , Cloreto de Sódio , Austrália , Composição de Bases , DNA Arqueal/genética , Genes Arqueais , Hibridização de Ácido Nucleico , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNARESUMO
A Gram-stain-negative, non-motile, pleomorphic rod-shaped, orange-red-pigmented, facultatively aerobic and haloalkaliphilic archaeon, strain MK13-1T, was isolated from commercial rock salt imported from Pakistan. The NaCl, pH and temperature ranges for growth of strain MK13-1T were 3.0-5.2âM NaCl, pH 8.0-11.0 and 15-50 °C, respectively. Optimal growth occurred at 3.2-3.4âM NaCl, pH 9.0-9.5 and 45 °C. Addition of Mg2+ was not required for growth. The major polar lipids of the isolate were C20C20 and C20C25 archaeol derivatives of phosphatidylglycerol and phosphatidylglycerol phosphate methyl ester. Glycolipids were not detected. The DNA G+C content was 64.1âmol%. The 16S rRNA gene sequence of strain MK13-1T was most closely related to those of the species of the genus Halorubrum, Halorubrum luteum CECT 7303T (95.9% similarity), Halorubrum alkaliphilum JCM 12358T (95.3%), Halorubrum kocurii JCM 14978T (95.3%) and Halorubrum lipolyticum JCM 13559T (95.3%). The rpoB' gene sequence of strain MK13-1T had < 90% sequence similarity to those of other members of the genus Halorubrum. Based on the phylogenetic analysis and phenotypic characterization, strain MK13-1T may represent a novel species of the genus Halorubrum, for which the name Halorubrum gandharaense sp. nov. is proposed, with the type strain MK13-1T ( = JCM 17823T = CECT 7963T).
Assuntos
Halorubrum/classificação , Filogenia , Cloreto de Sódio , Composição de Bases , DNA Arqueal/genética , Halorubrum/genética , Halorubrum/isolamento & purificação , Dados de Sequência Molecular , Paquistão , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , TemperaturaRESUMO
Two agar-degrading halophilic archaeal strains, 62 E(T) and 197 A, were isolated from commercial salt samples. Cells were non-motile cocci, approximately 1.2-2.0 µm in diameter and stained Gram-negative. Colonies were pink-pigmented. Strain 62 E(T) was able to grow with 24-30% (w/v) NaCl (optimum, 27%), at pH 6.5-8.5 (optimum, pH 7.5) and at 22-47 °C (optimum, 42 °C). The 16S rRNA gene sequences of strains 62 E(T) and 197 A were identical, and the level of DNA-DNA relatedness between them was 90 and 90% (reciprocally). The closest relative was Halococcus saccharolyticus JCM 8878(T) with 99.7% similarity in 16S rRNA orthologous gene sequences, followed by Halococcus salifodinae JCM 9578(T) (99.6%), while similarities with other species of the genus Halococcus were equal to or lower than 95.1%. The rpoB' gene tree strongly supported that the two strains were members of the genus Halococcus . Mean DNA-DNA relatedness between strain 62 E(T) and H. saccharolyticus JCM 8878(T) and H. salifodinae JCM 9578(T) was 46 and 44%, respectively. The major polar lipids were archaeol derivatives of phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, derived from both C20C20 and C20C25 archaeol, and sulfated diglycosyl archaeol-1. Several unidentified glycolipids were present. Based on the phenotypic and phylogenetic analyses, the isolates are considered to represent a novel species of the genus Halococcus , for which the name Halococcus agarilyticus sp. nov. is proposed. The type strain is 62 E(T) (â=âJCM 19592(T)â=KCTC 4143(T)).
Assuntos
Halococcus/classificação , Filogenia , Cloreto de Sódio , Ágar , Composição de Bases , DNA Arqueal/genética , Genes Arqueais , Glicolipídeos/química , Halococcus/genética , Halococcus/isolamento & purificação , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Fosfatidilgliceróis/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNARESUMO
Three halophilic archaeal strains, MH2-243-1(T), MH2-93-1 and MH2-91-1 were isolated from commercial salt samples from Japan, Australia, and Bolivia. Strain MH2-243-1(T) was able to grow in the presence of 12-30% (w/v) NaCl (optimum, 18% NaCl), at pH 4.5-7.0 (optimum, pH 6.0) and at 20-60 °C (optimum, 40 °C). Strains MH2-91-1 and MH2-93-1 grew in slightly different ranges. The orthologous 16S rRNA gene sequences of the three strains were almost identical (99.8-99.9% similarities), and the closest relative was Salarchaeum japonicum JCM 16327(T) with 94.2-94.3% 16S rRNA gene sequence similarities, followed by strains of members of the closely related genera Halobacterium and Halarchaeum . The RNA polymerase subunit B' gene (rpoB') sequence also showed the highest similarity (86.6%) to that of Salarchaeum japonicum JCM 16327(T). The DNA G+C contents of strains MH2-243-1(T), MH2-93-1 and MH2-91-1 were 68.5, 68.8 and 68.3 mol%, respectively. DNA-DNA relatedness values amongst the three strains were 97-99%. The polar lipids of the three strains were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, and at least seven unidentified glycolipids. The polar lipid composition differed from those of Salarchaeum japonicum and species of the genera Halobacterium and Halarchaeum . Based on the phenotypic and phylogenetic analyses, it is proposed that the isolates represent a novel species of a new genus, for which the name Halocalculus aciditolerans gen. nov., sp. nov. is proposed. The type strain of the type species is MH2-243-1(T) (â=âJCM 19596(T)â=KCTC 4149(T)) isolated from solar salt produced in Japan. MH2-93-1 (â=âJCM 19595) and MH2-91-1 (â=âJCM 19594) are additional strains of the type species.
Assuntos
Halobacteriaceae/classificação , Filogenia , Cloreto de Sódio , Austrália , Bolívia , DNA Arqueal/genética , Genes Arqueais , Glicolipídeos/química , Halobacteriaceae/genética , Halobacteriaceae/isolamento & purificação , Japão , Lipídeos/química , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNARESUMO
Three moderately acidophilic, halophilic archaeal strains, MH1-243-3T, MH1-243-5 and MH1-243-6, were isolated from a commercial salt sample made from seawater in Okinawa, Japan. Cells of the three strains were pleomorphic and stained Gram-negative. Colonies of the strains were orange-red-pigmented. Strain MH1-243-3T was able to grow at 15-27 % (w/v) NaCl (optimum 24 °C), at pH 4.5-6.5 (pH 5.5) and at 35-50 °C (45 °C). Strains MH1-243-5 and MH1-243-6 grew within slightly different ranges (shown in text). The 16S rRNA gene sequences of the three strains were identical, and the closest phylogenetic relative was Halarchaeum salinum MH1-34-1T with 97.0 % similarity. The rpoB' gene sequences of the three strains were also identical, and the closest phylogenetic relative was Halarchaeum acidiphilum JCM 16109T with 92.0 % similarity. The DNA G+C content of MH1-243-3T, MH1-243-5 and MH1-243-6 was 65.2âmol%. The levels of DNA-DNA relatedness amongst the three strains were 84.1-99.8 %, while that between MH1-243-3T and H. salinum MH1-34-1T was 30.6 % and 31.6 % (reciprocally), and those between MH1-243-3T and type strains of other species in the genus Halarchaeum were 42.3-29.4 %. Based on the phenotypic, genotypic and phylogenetic analyses, it is proposed that the isolates should represent a novel species of the genus Halarchaeum, for which the name Halarchaeum grantii sp. nov. is proposed. The type strain is MH1-243-3T ( = JCM 19585T = KCTC 4142T), isolated from commercial sea salt produced in Okinawa, Japan. MH1-243-5 ( = JCM 19586) and MH1-243-6 ( = JCM 18422) are additional strains of the species.
RESUMO
A nanoformulation composed of a ribosome inactivating protein-curcin and a hybrid solid lipid nanovector has been devised against glioblastoma. The structurally distinct nanoparticles were highly compatible to human endothelial and neuronal cells. A sturdy drug release from the particles, recorded upto 72 h, was reflected in the time-dependent toxicity. Folate-targeted nanoparticles were specifically internalized by glioma, imparting superior toxicity and curbed an aggressively proliferating in vitro 3D cancer mass in addition to suppressing the anti-apoptotic survivin and cell matrix protein vinculin. Combined with the imaging potential of the encapsulated dye, the nanovector emanates as a multifunctional anti-cancer system.
Assuntos
Neoplasias Encefálicas , Glioblastoma , Lipídeos , Imagem Molecular , Nanoestruturas/química , Proteínas Inativadoras de Ribossomos Tipo 1 , Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Proteínas Inibidoras de Apoptose/metabolismo , Lipídeos/química , Lipídeos/farmacocinética , Lipídeos/farmacologia , Proteínas de Neoplasias/metabolismo , Neurônios/metabolismo , Neurônios/patologia , Proteínas Inativadoras de Ribossomos Tipo 1/química , Proteínas Inativadoras de Ribossomos Tipo 1/farmacocinética , Proteínas Inativadoras de Ribossomos Tipo 1/farmacologia , Survivina , Vinculina/metabolismoRESUMO
A thermophilic bacterium, strain Sueoka(T), was isolated from steamed Japanese cedar chips from a lumber mill in Gobo, Japan. The strain was able to grow on carboxymethyl cellulose at 60 °C, was Gram-stain-negative, and grew between 40.0 and 67.5 °C (optimum at 55 °C) and between pH 3.5 and 6.5 (optimum at pH 4.8). Comparative analysis of 16S rRNA gene sequences revealed 91.9â, 90.9â, and 90.8% similarity to Alicyclobacillus macrosporangiidus(T), Alicyclobacillus pomorum(T), and Alicyclobacillus acidocaldarius(T), respectively. The major quinone was MK-7 and the predominant cellular fatty acids were ω-cyclohexane C19 : 0 and ω-cyclohexane C17 : 0. The DNA G+C content was 60.8 mol%. Based on the results of this study, strain Sueoka(T) is a novel species of the genus Alicyclobacillus, and the namehttp://dx.doi.org/10.1601/nm.5071Alicyclobacillus cellulosilyticus sp. nov. (type strain Sueoka(T)â = JCM 18487(T) â= KCTC 33007(T)) is proposed.
Assuntos
Alicyclobacillus/classificação , Cryptomeria/microbiologia , Filogenia , Madeira/microbiologia , Alicyclobacillus/genética , Alicyclobacillus/isolamento & purificação , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Ácidos Graxos/química , Japão , Dados de Sequência Molecular , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMO
BACKGROUND: Gliomas have been termed recurrent cancers due to their highly aggressive nature. Their tendency to infiltrate and metastasize has posed significant roadblocks to in attaining fool proof treatment solutions. An initiative to curb such a scenario was successfully demonstrated in vitro, utilizing a multi-conceptual gold nanoparticle based photo-thermal and drug combination therapy. METHODS: Gold nanoparticles (Au NPs) were synthesized with a highly environmentally benign process. The Au NPs were PEGylated and conjugated with folate and transferrin antibody to achieve a dual targeted nano-formulation directed towards gliomas. Curcin, a type 1 ribosome inactivating protein, was attached to the Au NPs as the drug candidate, and its multifarious toxic aspects analyzed in vitro. NIR photo-thermal properties of the Au nano-conjugates were studied to selectively ablate the glioma cancer colonies. RESULTS: Highly cyto-compatible, 10-15nm Au NP conjugates were synthesized with pronounced specificity towards gliomas. Curcin was successfully conjugated to the Au NPs with pH responsive drug release. Prominent toxic aspects of curcin, such as ROS generation, mitochondrial and cytoskeletal destabilization were witnessed. Excellent photo-thermal ablation properties of gold nanoparticles were utilized to completely disrupt the cancer colonies with significant precision. CONCLUSION: The multifunctional nanoconjugate projects its competence in imparting complete arrest of the future proliferation or migration of the cancer mass. GENERAL SIGNIFICANCE: With multifunctionality the essence of nanomedicine in recent years, the present nanoconjugate highlights itself as a viable option for a multimodal treatment option for brain cancers and the like.
Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Ouro/administração & dosagem , Nanopartículas Metálicas/administração & dosagem , Proteínas Inativadoras de Ribossomos Tipo 1/administração & dosagem , Células Cultivadas , Humanos , Espécies Reativas de Oxigênio/metabolismo , TricotecenosRESUMO
An agar-degrading archaeon Halococcus sp. 197A was isolated from a solar salt sample. The agarase was purified by hydrophobic column chromatography using a column of TOYOPEARL Phenyl-650 M. The molecular mass of the purified enzyme, designated as Aga-HC, was ~55 kDa on both SDS-PAGE and gel-filtration chromatography. Aga-HC released degradation products in the order of neoagarohexose, neoagarotetraose and small quantity of neoagarobiose, indicating that Aga-HC was a ß-type agarase. Aga-HC showed a salt requirement for both stability and activity, being active from 0.3 M NaCl, with maximal activity at 3.5 M NaCl. KCl supported similar activities as NaCl up to 3.5 M, and LiCl up to 2.5 M. These monovalent salts could not be substituted by 3.5 M divalent cations, CaCl2 or MgCl2. The optimal pH was 6.0. Aga-HC was thermophilic, with optimum temperature of 70 °C. Aga-HC retained approximately 90 % of the initial activity after incubation for 1 hour at 65-80 °C, and retained 50 % activity after 1 hour at 95 °C. In the presence of additional 10 mM CaCl2, approximately 17 % remaining activity was detected after 30 min at 100 °C. This is the first report on agarase purified from Archaea.
Assuntos
Proteínas Arqueais/metabolismo , Glicosídeo Hidrolases/metabolismo , Halococcus/enzimologia , Proteínas Arqueais/química , Estabilidade Enzimática , Glicosídeo Hidrolases/química , Especificidade por SubstratoRESUMO
Two halophilic moderately acidophilic archaeal strains, MH1-136-2(T) and MH1-370-1 were isolated from commercial salt samples made from seawater in Japan and Indonesia, respectively. Cells of the two strains were pleomorphic and Gram-stain-negative. Strain MH1-136-2(T) was pink pigmented, while MH1-370-1 was orange-red pigmented. Strain MH1-136-2(T) was able to grow at 9-30â% (w/v) NaCl (with optimum, 21â% NaCl, w/v) at pH 4.5-6.2 (optimum, pH 5.2-5.5) and at 18-55 °C (optimum, 45 °C). Strain MH1-370-1 was able to grow at 12-30â% (w/v) NaCl (optimum, 18â%, w/v) at pH 4.2-6.0 (optimum, pH 5.2-5.5) and 20-50 °C (optimum, 45 °C). Strain MH1-136-2(T) required at least 1 mM Mg(2+), while MH1-370-1 required at least 10 mM for growth. Both strains reduced nitrate and nitrite under aerobic conditions. The 16S rRNA gene sequences of strains MH1-136-2(T) and MH1-370-1 were identical, and the closest relative was Halarchaeum rubridurum MH1-16-3(T) with 98.3â% similarity. The level of DNA-DNA relatedness between these strains was 90.9â% and 92.4â% (reciprocally), while that between MH1-136-2(T) and Halarchaeum acidiphilum MH1-52-1(T), Halarchaeum salinum MH1-34-1(T) and Halarchaeum rubridurum MH1-16-3(T) was 37.7â%, 44.3â% and 41.1â% (each an average), respectively. Based on the phenotypic, genotypic and phylogenetic analyses, it is proposed that the isolates represent a novel species of the genus Halarchaeum, for which the name Halarchaeum nitratireducens sp. nov. is proposed. The type strain is MH1-136-2(T) (â=âJCM 16331(T)â=âCECT 7573(T)) isolated from solar salt produced in Japan.
Assuntos
Halobacteriaceae/classificação , Filogenia , Água do Mar/microbiologia , Cloreto de Sódio , Composição de Bases , DNA Arqueal/genética , Halobacteriaceae/genética , Halobacteriaceae/isolamento & purificação , Indonésia , Japão , Lipídeos/química , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Pigmentação , RNA Ribossômico 16S/genéticaRESUMO
A novel halophilic strain, BNERC31(T), was isolated from solar salt, 'Sel marin de Guérande', imported from France. Colonies on agar medium containing soluble starch, sodium citrate, sodium glutamate and inorganic salts were non-pigmented and transparent, while cells obtained by centrifuging liquid cultures were red-pigmented. Cells of strain BNERC31(T) were non-motile, pleomorphic, stained Gram-negative and lysed in distilled water. Growth occurred with 20-30â% (w/v) NaCl (optimum, 25â%, w/v), with 0-500 mM MgCl2 (optimum, 10 mM), at pH 6.0-8.5 (optimum, pH 7.0) and at 25-55 °C (optimum, 40 °C). Growth was dependent on soluble starch, and inhibited completely by 0.5â% organic nutrients, such as Casamino acids or yeast extract. The DNA G+C content was 64.1 mol%. Strain BNERC31(T) possessed at least two heterogeneous 16S rRNA genes, and the sequence of the orthologous gene (preceded by the dihydroorotate oxidase gene, pyrD) showed the highest similarity (96.5â%) to that of Haloarcula marismortui JCM 8966(T). The RNA polymerase subunit B' gene sequence showed the highest similarity (91.7â%) to that of Haloarcula amylolytica JCM 13557(T). The polar lipids of strain BNERC31(T) were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate, diglycosyl diether and sulfated diglycosyl diether, similar to those of species of the genus Halomicrobium. The phenotypic and phylogenetic characteristics showed that strain BNERC31(T) differed from species of the genera Haloarcula and Halomicrobium and indicated that it represents a novel species in a new genus, for which the name Halomicroarcula pellucida gen. nov., sp. nov. is proposed. The type strain of the type species is BNERC31(T) (â=âJCM 17820(T)â=âCECT 7537(T)).