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1.
Int J Syst Evol Microbiol ; 69(10): 3068-3073, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31310199

RESUMO

The taxonomic position of 'Actinomadura roseorufa' LMG 30035T, a semduramicin-producing mutant of strain ATCC 53666P, which was isolated from a soil sample collected in Yamae Village, Kamamoto, Japan, was clarified in the present study using a polyphasic approach. This Gram-positive, aerobic actinomycete formed a well-developed, extensively branched, non-fragmenting substrate and aerial mycelia which differentiated into single, smooth-appearing spores. Based on analysis of nearly complete 16S rRNA gene sequence, strain LMG 30035T was found to be closely related to the type strains of Actinomadura fibrosa ATCC 49459T (98.88 %) and Actinomadura formosensis JCM 7474T (98.82 %) (pairwise similarity values in parentheses). Digital DNA-DNA hybridisation experiments revealed unambiguously that strain LMG 30035T represents a novel Actinomadura species (OrthoANIu values less than 83.1 %; dDDH values less than 27.2 % with type strains of validly named Actinomadura species). Analysis of the cell wall revealed the presence of meso-diaminopimelic acid in the peptidoglycan. The whole-cell sugars were glucose, madurose, galactose, ribose and rhamnose. The major polar lipids included phosphatidylinositol and diphosphatidylglycerol. The predominant menaquinones were MK-9(H6), MK-9(H8), MK-9(H4) and MK-9(H2). The major fatty acids were C16 : 00, 10-methyl C18 : 0, C18 : 1 ω9c and C18 : 00. The DNA G+C content of its genome was 72.5 mol%. In summary, these characteristics distinguish strain LMG 30035T from validly named species of the genus Actinomadura, and therefore, we propose to classify this strain formally as the novel species Actinomadura roseirufa sp. nov. with LMG 30035T (=CECT 9808T,=ATCC 53664T) as the type strain.


Assuntos
Actinobacteria/classificação , Nigericina/análogos & derivados , Filogenia , Microbiologia do Solo , Actinobacteria/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Ionóforos , Japão , Nigericina/metabolismo , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
2.
Food Chem ; 300: 125194, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31325749

RESUMO

The effects of near freezing temperature (NFT) storage at -1.9 °C on cell wall degradation of 'Shushanggan' apricot was studied comparing to 0 °C and 5 °C storage. Our results indicated that NFT storage strongly inhibited the solubilization of Na2CO3-soluble pectin and cellulose, by the suppression of cell wall modifying enzymes (polygalacturonase, ß-Galactosidase, pectin methyl esterase and cellulase) and related genes expressions. The loss of side chains was the main modification in CDTA (Cyclohexane-diamine-tetraacetic Acid)-soluble pectin during storage and made the main contribution to the softening of apricot, while the loss of side chain was suppressed by NFT storage. Microscopic observation showed that NFT storage delayed the degradation of pectin fraction and protected cell wall structure from loosing. This study proves that NFT storage is an effective technology to suppress the cell wall polysaccharides degradation and ultrastructure modification of apricot.


Assuntos
Parede Celular/ultraestrutura , Armazenamento de Alimentos/métodos , Polissacarídeos/química , Prunus armeniaca/química , Hidrolases de Éster Carboxílico/química , Hidrolases de Éster Carboxílico/metabolismo , Parede Celular/química , Parede Celular/metabolismo , Celulose/química , Temperatura Baixa , Congelamento , Frutas/química , Frutas/citologia , Frutas/ultraestrutura , Pectinas/química , Células Vegetais/química , Células Vegetais/ultraestrutura , Poligalacturonase/química , Poligalacturonase/metabolismo , Polissacarídeos/metabolismo , Prunus armeniaca/citologia , Solubilidade , beta-Galactosidase/química , beta-Galactosidase/metabolismo
3.
Int J Syst Evol Microbiol ; 69(10): 3093-3099, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31329533

RESUMO

A novel bacterial strain, designated NEAU-SA2T, was isolated from forest soil collected from the Zhangjiajie city, Hunan Province, PR China and characterised using a polyphasic approach. The cells were aerobic, Gram-stain-positive, non-flagellated and rod-coccus-shaped. The strain grew optimally at 28 °C, pH 7.0 and with 0 % NaCl (w/v). Phylogenetic analysis based on the 16S rRNA gene sequence indicated that the organism should be assigned to the genus Arthrobacter and was closely related to Arthrobacter cupressi DSM 24664T (98.89 %) and Arthrobacter silvisoli CCTCC AB 2017271T (98.41 %), which was further confirmed by multilocus sequence analysis. The major cellular fatty acids were anteiso-C15 : 0, anteiso-C17 : 0 and C16 : 0; MK-9(H2) was the predominant respiratory quinone. The polar lipids comprised diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and an unidentified glycolipid. The peptidoglycan type was A3α, and the cell-wall sugars were glucose and galactose. The genomic G+C content of strain NEAU-SA2T was 67.04 mol%. The average nucleotide identity values between NEAU-SA2T and A. cupressi DSM 24664T and A. silvisoli CCTCC AB 2017271T were 88.57-90.94 %. The digital DNA-DNA hybridisation values between strain NEAU-SA2T and its most closely related species were 37.00 and 41.10 %, respectively, again indicating that they belong to different taxa. Therefore, strain NEAU-SA2T represents a novel species of the genus Arthrobacter, for which the name Arthrobacter celericrescens sp. nov. is proposed. The type strain is NEAU-SA2T (=DSM 106718T=CCTCC AB 2017272T).


Assuntos
Arthrobacter/classificação , Florestas , Filogenia , Microbiologia do Solo , Arthrobacter/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , China , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
4.
Food Chem ; 298: 124745, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260966

RESUMO

The chemical and sensory profiles of wines prepared from Cabernet Sauvignon grapes at different ripening stages vary greatly. Here, the soluble cell wall carbohydrate (SCWC) and phenolic profiles of wines were analyzed in parallel with the sensory evaluation of their mouthfeel and taste characteristics. Both SCWCs and phenolic compounds correlated with wine mouthfeel. When analyses were extended to specific classes of cell wall carbohydrates, it was shown that rhamnogalacturonan I/II, arabinan, arabinogalactan types I and II and xyloglucan from grapes were the key determinants of overall mouthfeel descriptors, particularly viscosity, astringency and roughness, whereas heteromannan from grapes was associated with mouth coating and chalkiness. A perceived sour taste was notably associated with higher homogalacturonan contents. This finding provides insights into the contributions of non-phenolic compounds to wine mouthfeel. The data provide opportunities for the development of simple monosaccharide marker assays to monitor major mouthfeel characteristics in red wines.


Assuntos
Carboidratos/análise , Parede Celular/química , Paladar , Vitis/química , Vinho/análise , Adstringentes/análise , Galactanos/análise , Humanos , Peso Molecular , Boca , Pectinas/análise , Fenóis/análise
5.
Chem Commun (Camb) ; 55(57): 8329-8332, 2019 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-31257378

RESUMO

Cell imaging heavily depends on fluorescent labels typically incompatible with Raman microscopy. The europium(iii) complex based on dipicolinic acid (DPA) presented here is an exception from this rule. Although its luminescence bands are very narrow, their intensity is comparable to the background Raman bands. This makes it complementary to less luminous compounds referred to as Raman tags. Through several examples we show that the complex provides a morphological context in otherwise unstained cells, thus acting as a spectral-counterstaining agent.


Assuntos
Complexos de Coordenação/química , Análise Espectral Raman , Candida albicans/metabolismo , Parede Celular/química , Células Epiteliais/química , Células Epiteliais/citologia , Európio/química , Células HeLa , Humanos , Microscopia de Fluorescência , Ácidos Picolínicos/química
6.
Plant Sci ; 286: 49-56, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31300141

RESUMO

Progress in the functional biochemical analysis of plant glycosyltransferases (GTs) has been slow because plant GTs are generally membrane proteins, operate as part of larger, multimeric complexes, and utilize a vast complexity of substrate acceptors. Therefore, the field would benefit from development of adequate high throughput expression as well as product detection and characterization techniques. Here we review current approaches to tackle such obstacles and suggest a new path forward: nucleic acid programmable protein arrays (NAPPA) with liquid sample desorption ionization (LS-DESI-MS) mass spectrometry. NAPPA utilizes in vitro transcription and translation to produce epitope-tagged fusion proteins from cloned GT cDNAs. LS-DESI is a soft ionization technique that allows rapid and sensitive MS-based product characterization in situ. Coupling both approaches provides the opportunity to examine individual GT functions as well as protein-protein interactions. Furthermore, advances in automated oligosaccharide synthesis and lipid nanodisc technology should allow testing of plant GT activity in presence of numerous substrate acceptors and lipid environments in a high throughput fashion. Thus, NAPPA-DESI-MS has great potential to make headway in biochemical characterization of the large number of plant GTs.


Assuntos
Parede Celular/química , Ensaios de Triagem em Larga Escala/métodos , Plantas/química , Polissacarídeos/biossíntese , Análise Serial de Proteínas/métodos , Glicosiltransferases/análise , Espectrometria de Massas/métodos , Proteínas de Plantas/análise , Plantas/enzimologia
7.
Int J Syst Evol Microbiol ; 69(9): 2862-2869, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31274399

RESUMO

Four Gram-stain positive, rod-shaped bacterial isolates, strains JZ R-183T, JZ RK-117, DI-46 and JZ R-35T, were recovered from bulk tank raw cow's milk from three different dairy farms in Germany. Analysis of their 16S rRNA gene sequences indicated that these isolates belonged to the family Micrococcaceae, closely related to the genera Arthrobacter, Neomicrococcus,Glutamicibacter and Citricoccus. The 16S rRNA gene sequence similarity between the isolates and the next related type strains was below 97.3 %. Phylogenetic analysis of 16S rRNA, recA and gyrB genes revealed that these isolates formed two different groups in an independent cluster within the family Micrococcaceae. Chemotaxonomic analyses determined anteiso-C15 : 0 as predominant fatty acid, but also large amounts of iso-C15 : 0, iso-C16 : 0 and iso-C17 : 0 were detected. The menaquinones MK-9(H2) and MK-7(H2) were present in all of the isolates and the polar lipid pattern contained the phospholipids diphosphatidylglycerol, phosphatidylglycerol and phosphatidylinositol and a glycolipid. The peptidoglycan type of the isolates was A4α, with alanine, lysine and glutamate as dominating cell wall amino acids. The fatty acid and menaquinone profile differentiated the strains from the genera Arthrobacter, Neomicrococcus,Citricoccus and Glutamicibacter. The results of phylogenetic, phenotypic and chemotaxonomic analyses indicated that the isolates belonged to two novel species of a novel genus, for which the names Galactobacter caseinivorans gen. nov., sp. nov. and Galactobacter valiniphilus sp. nov. are proposed. The type strains are JZ R-183T (=DSM 107700T=LMG 30902T) and JZ R-35T (=DSM 107699T=LMG 30901T).


Assuntos
Micrococcaceae/classificação , Leite/microbiologia , Filogenia , Animais , Carga Bacteriana , Técnicas de Tipagem Bacteriana , Composição de Bases , Bovinos/microbiologia , Parede Celular/química , DNA Bacteriano/genética , Ácidos Graxos/química , Feminino , Alemanha , Glicolipídeos/química , Micrococcaceae/isolamento & purificação , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
8.
Int J Syst Evol Microbiol ; 69(9): 2884-2891, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31310194

RESUMO

A novel endophytic actinomycete strain AZ1-13T was isolated from roots of Azadirachta indica, and its taxonomic position was investigated using a polyphasic approach. Pairwise 16S rRNA gene sequence similarities of strain AZ1-13T and its closest species, Jishegella zingiberis PLAI1-1T and Micromonospora endophytica 202201T, were 99.7 and 99.2 %, respectively. Phylogenetic analyses of the family Micromonosporaceae based on 16S rRNA gene sequences indicated strains AZ1-13T and J. zingiberis PLAI1-1Tare located within the genus Micromonospora. The approximate genome size of the strain was 5.96 Mb with 71.9 mol% of G+C content. The strain AZ1-13T exhibited ANIb values of 87.4 % with J. zingiberis PLAI1-1T and 85.1 % with M. endophytica 202201T. Chemotaxonomic characteristics of strain AZ1-13T were consistent within the genus Micromonospora: cell-wall peptidoglycan of the strain contained meso-diaminopimelic acid; glucose, mannose, ribose and xylose are presented as the whole-cell sugars; the predominant menaquinones were MK-9(H4) and MK-9(H6); major cellular fatty acids were iso-C15 : 0, 10-methyl C17 : 0, C17 : 0, anteiso-C17 : 0 and iso-C17 : 1ω8c; diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylinositol were detected as distinguished phospholipids. Based on phenotypic properties, phylogeny and genomic data, the strain AZ1-13T could be distinguished from its closest neighbours, representing a novel species of the genus Micromonospora, for which the name Micromonospora radicis sp. nov. is proposed. The type strain is AZ1-13T (=KCTC 39786T=NBRC 112324T=JCM 32147T = TISTR 2404T). This study also proposed that J. zingiberisis transferred to the genus Micromonospora as Micromonospora zingiberis comb. nov. (type strain PLAI1-1T=TBRC 7644T=NBRC 113144T=JCM 32592T).


Assuntos
Azadirachta/microbiologia , Micromonospora/classificação , Filogenia , Raízes de Plantas/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Micromonospora/isolamento & purificação , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Tailândia , Vitamina K 2/análogos & derivados , Vitamina K 2/química
9.
Anal Chim Acta ; 1076: 32-47, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31203962

RESUMO

Electroactive microorganisms possess the unique ability to transfer electrons to or from solid phase electron conductors, e.g., electrodes or minerals, through various physiological mechanisms. The processes are commonly known as extracellular electron transfer and broadly harnessed in microbial electrochemical systems, such as microbial biosensors, microbial electrosynthesis, or microbial fuel cells. Apart from a few model microorganisms, the nature of the microbe-electrode conductive interaction is poorly understood for most of the electroactive species. The interaction determines the efficiency and a potential scaling up of bioelectrochemical systems. Gram-positive bacteria generally have a thick electron non-conductive cell wall and are believed to exhibit weak extracellular electron shuttling activity. This review highlights reported research accomplishments on electroactive Gram-positive bacteria. The use of electron-conducting polymers as mediators is considered as one promising strategy to enhance the electron transfer efficiency up to application scale. In view of the recent progress in understanding the molecular aspects of the extracellular electron transfer mechanisms of Enterococcus faecalis, the electron transfer properties of this bacterium are especially focused on. Fundamental knowledge on the nature of microbial extracellular electron transfer and its possibilities can provide insight in interspecies electron transfer and biogeochemical cycling of elements in nature. Additionally, a comprehensive understanding of cell-electrode interactions may help in overcoming insufficient electron transfer and restricted operational performance of various bioelectrochemical systems and facilitate their practical applications.


Assuntos
Elétrons , Bactérias Gram-Positivas/química , Parede Celular/química , Eletrodos , Hidrogéis/química , Proteínas de Membrana/química , Oxirredução , Polímeros/química
10.
Carbohydr Polym ; 219: 181-190, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31151515

RESUMO

Water-soluble fraction (WSF), CDTA-soluble fraction (CSF), sodium carbonate-soluble fraction (SSF), loosely-bonding KOH-soluble fractions (LKF) and tightly-bonding KOH-soluble fractions (TKF) were sequentially extracted from tomato cell wall polysaccharides. Physicochemical properties and functional bioactivities of these different bonding state tomato fruit polysaccharides (DBTP) were investigated. WSF, CSF and SSF were identified as pectic polysaccharides, while LKF and TKF were identified as hemicellulose. WSF, possessing plenty of galacturonic acids, was considered as an aggregative of linear homogalacturonan with extremely high molecular weight. CSF and SSF, rich in neutral sugars side chains, contained abundant rhamnogalacturonan regions. These polysaccharides exhibited distinct surface morphology and special FTIR spectrums. Thermal analysis manifested that LKF and TKF exhibited higher thermal stability. WSF and SSF showed higher apparent viscosity and elasticity. Assays for functional bioactivities suggested that CSF and SSF displayed stronger antioxidant activities, while CSF, SSF and TKF exhibited higher hypolipidemic activities.


Assuntos
Parede Celular/química , Frutas , Lycopersicon esculentum , Polissacarídeos , Antioxidantes/farmacologia , Elasticidade , Frutas/citologia , Frutas/metabolismo , Hipolipemiantes/farmacologia , Lycopersicon esculentum/citologia , Lycopersicon esculentum/metabolismo , Pectinas/química , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Solubilidade , Viscosidade
11.
Phys Chem Chem Phys ; 21(27): 14571-14582, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31237595

RESUMO

This study is based on extensive MD simulations of a protein in a reverse micelle to mimic the effect of confinement on biomolecules. This permits the calculation of measurable quantities appearing in NQR and Nuclear Overhauser-NMR despite the high computational effort. We address the long-standing debate about the intermolecular NOE showing that absolute quantities derived from NOESY and ROESY spectra do indeed contain considerable long-range contributions, while ratios thereof are effectively short-ranged due to almost perfect compensation effects. Based on NQR relaxation times, we predict strong rotational retardation of interstitial water between the protein and the surfactant surface. The computed NOE to ROE ratio correlates fairly with experimental results. The solvation dynamics mapped onto the protein surface reflects the spatial heterogeneity of a cell-like system with slow water dynamics in proximity to the cell wall and almost bulk-like behaviour in the water core.


Assuntos
Micelas , Proteínas/metabolismo , Água/química , Parede Celular/química , Técnicas de Química Analítica , Espectroscopia de Ressonância Magnética , Simulação de Dinâmica Molecular , Proteínas/química
12.
Nat Commun ; 10(1): 2731, 2019 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-31227690

RESUMO

Many bacteria and most archaea possess a crystalline protein surface layer (S-layer), which surrounds their growing and topologically complicated outer surface. Constructing a macromolecular structure of this scale generally requires localized enzymatic machinery, but a regulatory framework for S-layer assembly has not been identified. By labeling, superresolution imaging, and tracking the S-layer protein (SLP) from C. crescentus, we show that 2D protein self-assembly is sufficient to build and maintain the S-layer in living cells by efficient protein crystal nucleation and growth. We propose a model supported by single-molecule tracking whereby randomly secreted SLP monomers diffuse on the lipopolysaccharide (LPS) outer membrane until incorporated at the edges of growing 2D S-layer crystals. Surface topology creates crystal defects and boundaries, thereby guiding S-layer assembly. Unsupervised assembly poses challenges for therapeutics targeting S-layers. However, protein crystallization as an evolutionary driver rationalizes S-layer diversity and raises the potential for biologically inspired self-assembling macromolecular nanomaterials.


Assuntos
Proteínas de Bactérias/química , Parede Celular/química , Glicoproteínas de Membrana/química , Caulobacter crescentus/química , Cristalização , Lipopolissacarídeos/química , Substâncias Macromoleculares/química , Nanoestruturas/química , Nanotecnologia/métodos
13.
Int J Syst Evol Microbiol ; 69(8): 2533-2540, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31215863

RESUMO

A novel actinobacterial strain, designated 16K104T, was isolated from desert soil collected from the Karakum Desert and characterized using a polyphasic approach to clarify its taxonomic position. Strain 16K104T was found to have chemotaxonomic and morphological properties consistent with classification in the genus Kribbella. The strain shared the highest 16S rRNA gene sequence similarity with Kribbella albertanoniae BC640T (99.2 %), and formed a branch with Kribbella antibiotica YIM 31530T in the 16S rRNA gene phylogenetic tree. Multilocus sequence analysis (MLSA) using five housekeeping genes (gyrB, rpoB, relA, recA and atpD) for comparing the strain with all Kribbella type strains showed that the MLSA distances of strain 16K104T to the closely related type strains of the genus were much higher than the 0.04 threshold. The organism was found to contain ll-diaminopimelic acid as the diagnostic diamino acid in the cell-wall peptidoglycan. The whole-cell sugars were identified as ribose and glucose. The major polar lipids were diphosphatidylglycerol, phosphatidylcholine, phosphatidylglycerol and phosphatidylinositol. The predominant menaquinone was MK-9(H4). The major fatty acids were iso-C16 : 0, anteiso-C15:0, iso-C15 : 0 and iso-C17 : 0. The results of digital DNA-DNA hybridization and average nucleotide identity analyses, in addition to MLSA phylogenetic distances, confirmed that the strain represents a novel species of the genus Kribbella, for which the name Kribbella turkmenica sp. nov. is proposed. The type strain is 16K104T (=JCM 32914T=KCTC 49224T).


Assuntos
Actinobacteria/classificação , Clima Desértico , Filogenia , Microbiologia do Solo , Actinobacteria/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , DNA Bacteriano/genética , Ácido Diaminopimélico/análise , Ácidos Graxos/química , Tipagem de Sequências Multilocus , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/análise , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Turcomenistão , Vitamina K 2/análogos & derivados , Vitamina K 2/química
14.
Anal Bioanal Chem ; 411(20): 5047-5062, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31172238

RESUMO

Diferulic (DFA) and triferulic acids (TriFA) acylate and cross-link plant cell wall polysaccharides, thereby being important structural elements within the cell wall, also affecting physicochemical properties of the isolated polysaccharides. Due to the large number of potential regio- and configurational isomers and due to the fact that oligoferulic acids are not commercially available as standard compounds, analysis of oligoferulic acids after alkaline hydrolysis is challenging. Eighteen di- and triferulic acids were synthesized both non-labeled as well as 13C-labeled. By using these standard compounds, a liquid chromatography-tandem mass spectrometry (LC-MS/MS) (electrospray ionization, negative mode)-based stable isotope dilution approach was developed, fully validated and applied to plant materials. Whereas this stable isotope dilution approach is most useful to analyze plant materials with complex matrices (especially lignified tissues), less complicated matrices may not require this approach. Therefore, an alternative LC-MS/MS-based method that is based on using a single internal standard compound only was developed, too, validated, and compared to the stable isotope dilution approach. Although the stable isotope dilution approach appears to be superior, plant samples with simple matrices can also be screened by using the single internal standard method developed here.


Assuntos
Biopolímeros/análise , Parede Celular/química , Cromatografia Líquida/métodos , Ácidos Cumáricos/química , Plantas/química , Espectrometria de Massas em Tandem/métodos , Espectroscopia de Ressonância Magnética , Reprodutibilidade dos Testes
15.
BMC Plant Biol ; 19(1): 271, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31226937

RESUMO

BACKGROUND: The heavy metal cadmium (Cd) accumulates in the environment due to anthropogenic influences. It is unessential and harmful to all life forms. The plant cell wall forms a physical barrier against environmental stress and changes in the cell wall structure have been observed upon Cd exposure. In the current study, changes in the cell wall composition and structure of Medicago sativa stems were investigated after long-term exposure to Cd. Liquid chromatography coupled to mass spectrometry (LC-MS) for quantitative protein analysis was complemented with targeted gene expression analysis and combined with analyses of the cell wall composition. RESULTS: Several proteins determining for the cell wall structure changed in abundance. Structural changes mainly appeared in the composition of pectic polysaccharides and data indicate an increased presence of xylogalacturonan in response to Cd. Although a higher abundance and enzymatic activity of pectin methylesterase was detected, the total pectin methylation was not affected. CONCLUSIONS: An increased abundance of xylogalacturonan might hinder Cd binding in the cell wall due to the methylation of its galacturonic acid backbone. Probably, the exclusion of Cd from the cell wall and apoplast limits the entry of the heavy metal into the symplast and is an important factor during tolerance acquisition.


Assuntos
Cádmio/toxicidade , Parede Celular/química , Medicago sativa/efeitos dos fármacos , Pectinas/química , Poluentes do Solo/toxicidade , Cromatografia Líquida , Perfilação da Expressão Gênica , Ácidos Hexurônicos/metabolismo , Espectrometria de Massas , Monossacarídeos/análise , Proteínas de Plantas/metabolismo , Caules de Planta/química , Polissacarídeos/química , Proteoma
16.
Int J Syst Evol Microbiol ; 69(9): 2632-2637, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31184567

RESUMO

A Gram-stain-positive, strictly aerobic, motile and rod-shaped bacterium, designated strain LJ137T, was isolated from the sediment of Taihu Lake in China. A polyphasic approach was used to investigate its taxonomic position. Strain LJ137T grew optimally at pH 7.5, at 37 °C and with 2.5 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain LJ137T was most closely related to the genera Ornithinibacillus and Oceanobacillus. The closest phylogenetic neighbours were Ornithinibacillus halophilus KCTC 13822T, Ornithinibacillus salinisoli LCB256T and Oceanobacillus limi KCTC 13823T, with 95.2, 96.5 and 95.6 % 16S rRNA gene sequence similarity, respectively. The peptidoglycan amino acid type was A4α (l-Lys-d-Asp). The major respiratory quinone was menaquinone-7 (MK-7). The polar lipids of strain LJ137T contained diphosphatidylglycerol, phosphatidylglycerol, three unidentified phospholipids, two aminophospholipids and one unidentified lipid. The G+C content of the genomic DNA was 40.4 mol%. The dominant cellular fatty acids were anteiso-C15 : 0, anteiso-C17 : 0 and iso-C15 : 0. Based on the phenotypic, chemotaxonomic, phylogenetic and genome sequence characteristics of this strain, a novel species, Ornithinibacillus gellani sp. nov., is proposed. The type strain is LJ137T (=CGMCC 1.13678T=NBRC 113552T). An emended description of the genus Ornithinibacillus is presented.


Assuntos
Bacillaceae/classificação , Sedimentos Geológicos/microbiologia , Lagos/microbiologia , Filogenia , Bacillaceae/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , China , DNA Bacteriano/genética , Ácidos Graxos/química , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
17.
Subcell Biochem ; 92: 417-469, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31214994

RESUMO

Actinobacteria is a group of diverse bacteria. Most species in this class of bacteria are filamentous aerobes found in soil, including the genus Streptomyces perhaps best known for their fascinating capabilities of producing antibiotics. These bacteria typically have a Gram-positive cell envelope, comprised of a plasma membrane and a thick peptidoglycan layer. However, there is a notable exception of the Corynebacteriales order, which has evolved a unique type of outer membrane likely as a consequence of convergent evolution. In this chapter, we will focus on the unique cell envelope of this order. This cell envelope features the peptidoglycan layer that is covalently modified by an additional layer of arabinogalactan . Furthermore, the arabinogalactan layer provides the platform for the covalent attachment of mycolic acids , some of the longest natural fatty acids that can contain ~100 carbon atoms per molecule. Mycolic acids are thought to be the main component of the outer membrane, which is composed of many additional lipids including trehalose dimycolate, also known as the cord factor. Importantly, a subset of bacteria in the Corynebacteriales order are pathogens of human and domestic animals, including Mycobacterium tuberculosis. The surface coat of these pathogens are the first point of contact with the host immune system, and we now know a number of host receptors specific to molecular patterns exposed on the pathogen's surface, highlighting the importance of understanding how the cell envelope of Actinobacteria is structured and constructed. This chapter describes the main structural and biosynthetic features of major components found in the actinobacterial cell envelopes and highlights the key differences between them.


Assuntos
Actinobacteria/citologia , Membrana Celular/química , Membrana Celular/metabolismo , Parede Celular/química , Parede Celular/metabolismo , Animais , Humanos , Mycobacterium tuberculosis/patogenicidade , Ácidos Micólicos/metabolismo , Peptidoglicano/metabolismo
18.
Subcell Biochem ; 92: 471-493, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31214995

RESUMO

The cell wall of archaea, as of any other prokaryote, is surrounding the cell outside the cytoplasmic membrane and is mediating the interaction with the environment. In this regard, it can be involved in cell shape maintenance, protection against virus, heat, acidity or alkalinity. Throughout the formation of pore like structures, it can resemble a micro sieve and thereby enable or disable transport processes. In some cases, cell wall components can make up more than 10% of the whole cellular protein. So far, a great variety of different cell envelope structures and compounds have be found and described in detail. From all archaeal cell walls described so far, the most common structure is the S-layer. Other archaeal cell wall structures are pseudomurein, methanochondroitin, glutaminylglycan, sulfated heteropolysaccharides and protein sheaths and they are sometimes associated with additional proteins and protein complexes like the STABLE protease or the bindosome. Recent advances in electron microscopy also illustrated the presence of an outer(most) cellular membrane within several archaeal groups, comparable to the Gram-negative cell wall within bacteria. Each new cell wall structure that can be investigated in detail and that can be assigned with a specific function helps us to understand, how the earliest cells on earth might have looked like.


Assuntos
Archaea/citologia , Parede Celular/química , Parede Celular/fisiologia , Proteínas Arqueais/química , Proteínas Arqueais/metabolismo , Transporte Biológico , Membrana Celular/química , Membrana Celular/metabolismo
19.
Int J Syst Evol Microbiol ; 69(8): 2486-2491, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31169487

RESUMO

The taxonomic position of an actinobacterium isolated from a desert soil sample collected from Badain Jaran Desert, designated as CPCC 204711T, was established using a polyphasic approach. Cells of the isolate were Gram-staining-positive, aerobic, non-motile cocci. Good growth was observed at 28 °C (range 20-40 °C), pH 7.0 (range pH 6.0-8.0) and 0-1 % NaCl concentration (range 0-5 %, w/v). Galactose, arabinose and ribose were detected as the sugar compositions in the whole cell hydrolysates. The peptidoglycan type was A3gamma (ll-Dpm-Gly). MK-9(H4) was detected as the predominant menaquinone, and diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, several unidentified glycolipids, and one unidentified amino-glycolipid were detected as the major polar lipids. The predominant fatty acid was anteiso-C15 : 0. The genomic DNA G+C content was 73.1 mol%. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain CPCC 204711T affiliated to the family Propionibacteriaceae, in which the strain formed a distinct phylogenetic lineage next to the genus Mariniluteicoccus, with the highest 16S rRNA gene sequence similarity of 96.0 % to Mariniluteicoccus endophyticus YIM 2617T. Both phylogenetic analysis and phenotypic characteristics supported that strain CPCC 204711T represents a novel species of a new genus in the family Propionibacteriaceae, for which the name Desertihabitans aurantiacus gen. nov., sp. nov. is proposed, with CPCC 204711T (=KCTC 39977T=DSM 105431T) as the type strain.


Assuntos
Clima Desértico , Filogenia , Propionibacteriaceae/classificação , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , China , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Glicolipídeos/química , Peptidoglicano/química , Fosfolipídeos/química , Propionibacteriaceae/isolamento & purificação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
20.
Food Chem ; 293: 358-367, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31151623

RESUMO

To better understanding the role of cell wall pectic polysaccharides (CWPs) on the formation of textural properties of carrot chips dried by instant controlled pressure drop technology (French for Détente Instantanée Contrôlée, DIC), the characteristics of CWPs from ground tissue (GT), junction of ground and vascular tissue (JT), and vascular tissue (VT) of carrot were investigated. Larger expansion volume was obtained in the carrot chips derived from GT, which accompanied with superior textural qualities compared with the chips derived from JT and VT. Remarkable differences were obtained in the amount of pectic fractions, galacturonic acid content, degree of methoxylation, sugar composition and linearity of CWPs that fractionated from different tissue zones of raw carrots. The characteristics of CWPs was confirmed to be a substantial factor that significantly affected the expansion ratio and textural properties of the DIC-dried carrot chips, which providing a mechanistic insight of the relationship between variation in CWPs and the expanding behaviors of DIC-dried fruits and vegetables.


Assuntos
Daucus carota/química , Polissacarídeos/química , Parede Celular/química , Manipulação de Alimentos/métodos , Ácidos Hexurônicos/análise , Pectinas/química , Polissacarídeos/análise , Pressão , Açúcares/análise
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