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1.
Nat Commun ; 11(1): 4692, 2020 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-32943624

RESUMO

Hemicelluloses, a family of heterogeneous polysaccharides with complex molecular structures, constitute a fundamental component of lignocellulosic biomass. However, the contribution of each hemicellulose type to the mechanical properties of secondary plant cell walls remains elusive. Here we homogeneously incorporate different combinations of extracted and purified hemicelluloses (xylans and glucomannans) from softwood and hardwood species into self-assembled networks during cellulose biosynthesis in a bacterial model, without altering the morphology and the crystallinity of the cellulose bundles. These composite hydrogels can be therefore envisioned as models of secondary plant cell walls prior to lignification. The incorporated hemicelluloses exhibit both a rigid phase having close interactions with cellulose, together with a flexible phase contributing to the multiscale architecture of the bacterial cellulose hydrogels. The wood hemicelluloses exhibit distinct biomechanical contributions, with glucomannans increasing the elastic modulus in compression, and xylans contributing to a dramatic increase of the elongation at break under tension. These diverging effects cannot be explained solely from the nature of their direct interactions with cellulose, but can be related to the distinct molecular structure of wood xylans and mannans, the multiphase architecture of the hydrogels and the aggregative effects amongst hemicellulose-coated fibrils. Our study contributes to understanding the specific roles of wood xylans and glucomannans in the biomechanical integrity of secondary cell walls in tension and compression and has significance for the development of lignocellulosic materials with controlled assembly and tailored mechanical properties.


Assuntos
Parede Celular/química , Celulose/química , Extratos Vegetais/química , Plantas/química , Polissacarídeos/química , Madeira/química , Configuração de Carboidratos , Sequência de Carboidratos , Catárticos/química , Citoesqueleto/química , Hidrogéis/química , Mananas , Xilanos/química
2.
Nat Commun ; 11(1): 4720, 2020 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-32948753

RESUMO

Cellulose, the most abundant biopolymer on earth, is a versatile, energy rich material found in the cell walls of plants, bacteria, algae, and tunicates. It is well established that cellulose is crystalline, although the orientational order of cellulose crystallites normal to the plane of the cell wall has not been characterized. A preferred orientational alignment of cellulose crystals could be an important determinant of the mechanical properties of the cell wall and of cellulose-cellulose and cellulose-matrix interactions. Here, the crystalline structures of cellulose in primary cell walls of onion (Allium cepa), the model eudicot Arabidopsis (Arabidopsis thaliana), and moss (Physcomitrella patens) were examined through grazing incidence wide angle X-ray scattering (GIWAXS). We find that GIWAXS can decouple diffraction from cellulose and epicuticular wax crystals in cell walls. Pole figures constructed from a combination of GIWAXS and X-ray rocking scans reveal that cellulose crystals have a preferred crystallographic orientation with the (200) and (110)/([Formula: see text]) planes preferentially stacked parallel to the cell wall. This orientational ordering of cellulose crystals, termed texturing in materials science, represents a previously unreported measure of cellulose organization and contradicts the predominant hypothesis of twisting of microfibrils in plant primary cell walls.


Assuntos
Parede Celular/química , Celulose/química , Plantas/química , Arabidopsis/química , Bryopsida/química , Cristalografia , Cristalografia por Raios X , Microfibrilas/química
3.
PLoS One ; 15(7): e0236586, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32726362

RESUMO

Short rotation woody biomass cultivars developed from fast-growing shrub species of willow (Salix spp.) have superior properties as perennial energy crops for the Northeast and Midwest US. However, the insect pest potato leafhopper (PLH) Empoasca fabae (Harris) can cause serious damage and reduce yield of susceptible genotypes. Currently, the willow cultivars in use display varying levels of susceptibility under PLH infestation. However, genes and markers for resistance to PLH are not yet available for marker-assisted selection in breeding. In this study, transcriptome differences between a resistant genotype 94006 (S. purpurea) and a susceptible cultivar 'Jorr' (S. viminalis), and their hybrid progeny were determined. Over 600 million RNA-Seq reads were generated and mapped to the Salix purpurea reference transcriptome. Gene expression analyses revealed the unique defense mechanism in resistant genotype 94006 that involves PLH-induced secondary cell wall modification. In the susceptible genotypes, genes involved in programed cell death were highly expressed, explaining the necrosis symptoms after PLH feeding. Overall, the discovery of resistance genes and defense mechanisms provides new resources for shrub willow breeding and research in the future.


Assuntos
Salix/genética , Transcriptoma , Animais , Apoptose/genética , Parede Celular/química , Parede Celular/metabolismo , Produtos Agrícolas , Perfilação da Expressão Gênica , Redes Reguladoras de Genes/genética , Genótipo , Hemípteros/fisiologia , Herbivoria , Interações Hospedeiro-Parasita/genética , Fenótipo , Análise de Componente Principal , RNA de Plantas/química , RNA de Plantas/metabolismo , Salix/parasitologia
4.
Food Chem ; 330: 127357, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32569943

RESUMO

Attenuated total reflectance Fourier transform spectroscopy (ATR-FTIR) was applied on fresh (NF), freeze-dried (FD) and cell wall materials (AIS) of raw and processed apples. These samples prepared from 36 apple sets and the corresponding 72 purees, issued from different varieties, agricultural practices, storage periods and processing conditions, were used to build models including exploratory analysis, supervised classification and multivariate calibration. Fresh and freeze-dried samples presented similar fingerprint spectral variations due to processing. ATR-FTIR directly on fresh purees satisfactorily predicted textural properties such as particle average size and volume (RPD > 3.0), while freeze-drying improved assessment of chemical (RPD > 3.2) and rheological (RPD > 3.1) parameters using partial least-squares regression. The assessment of texture and macrocomponents of purees can be obtained with a limited sample preparation. For research applications because of a need of sample preparation, changes of cell wall composition during fruit processing could be assessed in relationship with pectin degradation.


Assuntos
Parede Celular/química , Indústria de Processamento de Alimentos/métodos , Malus/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Calibragem , Análise de Alimentos/métodos , Análise de Alimentos/estatística & dados numéricos , Liofilização , Frutas/química , Análise dos Mínimos Quadrados , Malus/citologia , Tamanho da Partícula , Reologia , Espectroscopia de Infravermelho com Transformada de Fourier/estatística & dados numéricos
5.
Nature ; 582(7811): 294-297, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32523118

RESUMO

The primary structural component of the bacterial cell wall is peptidoglycan, which is essential for viability and the synthesis of which is the target for crucial antibiotics1,2. Peptidoglycan is a single macromolecule made of glycan chains crosslinked by peptide side branches that surrounds the cell, acting as a constraint to internal turgor1,3. In Gram-positive bacteria, peptidoglycan is tens of nanometres thick, generally portrayed as a homogeneous structure that provides mechanical strength4-6. Here we applied atomic force microscopy7-12 to interrogate the morphologically distinct Staphylococcus aureus and Bacillus subtilis species, using live cells and purified peptidoglycan. The mature surface of live cells is characterized by a landscape of large (up to 60 nm in diameter), deep (up to 23 nm) pores constituting a disordered gel of peptidoglycan. The inner peptidoglycan surface, consisting of more nascent material, is much denser, with glycan strand spacing typically less than 7 nm. The inner surface architecture is location dependent; the cylinder of B. subtilis has dense circumferential orientation, while in S. aureus and division septa for both species, peptidoglycan is dense but randomly oriented. Revealing the molecular architecture of the cell envelope frames our understanding of its mechanical properties and role as the environmental interface13,14, providing information complementary to traditional structural biology approaches.


Assuntos
Bacillus subtilis/citologia , Bacillus subtilis/ultraestrutura , Parede Celular/química , Parede Celular/ultraestrutura , Microscopia de Força Atômica , Staphylococcus aureus/citologia , Staphylococcus aureus/ultraestrutura , Bacillus subtilis/química , Viabilidade Microbiana , Peptidoglicano/química , Peptidoglicano/isolamento & purificação , Peptidoglicano/ultraestrutura , Staphylococcus aureus/química
6.
Food Chem ; 330: 127252, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32585587

RESUMO

Mycoprotein is a food ingredient from filamentous fungi rich in protein and fibre. This study investigated the protein bioaccessibility from the fungal cells by colourimetric assays in different mycoprotein formulations, following extraction methods and in vitro gastrointestinal digestion. The methods effects were further analysed by static laser light scattering, SDS-PAGE and optical-fluorescence microscopy. The extraction methods released a comparable proportion of protein (30 wt%) independent of sample concentration (10 wt% and 25 wt%), whereas the simulated digestions endpoints released a higher proportion of protein from the less concentrated (46 wt%). Furthermore, mechanical/physical processing had only a minor impact. Intestinal proteases promoted the most efficient protein release but without causing any apparent damage to the cell walls when viewed by microscopy. This suggested that the enzymes can diffuse through the cell walls, due to its porosity/permeability, and are the main factors responsible for the hydrolysis and bioaccessibility of protein from mycoprotein.


Assuntos
Proteínas Fúngicas/metabolismo , Animais , Disponibilidade Biológica , Parede Celular/química , Parede Celular/metabolismo , Fibras na Dieta/metabolismo , Digestão , Proteínas Fúngicas/química , Fungos/química , Fungos/metabolismo
7.
Arch Microbiol ; 202(9): 2373-2378, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32583126

RESUMO

A Gram-positive, endospore-forming, rod-shaped bacterium with a single flagellum, and a motile strain, designated CX253, was isolated from bioaerosols. The isolate is facultatively anaerobic, is able to grow at 25-45 â„ƒ (optimum 37 â„ƒ) and pH 6.5-10.0 (optimum 7.5), and can tolerate up to 5.0% NaCl (w/v) under aerobic conditions. The diagnostic diamino acid in the cell wall of strain CX253T is meso-diaminopimelic acid, while major isoprenoid quinone is menaquinone 6 (MK-6) along with a smaller amount of MK-7 (20%). The polar lipid profile is composed of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phospholipids and glycolipids. The major cellular fatty acid is iso-C15:0 and anteiso-C15:0. Phylogenetic analysis based on 16S rRNA gene and genome sequence grouped strain CX253T into the genus Bacillus. The strain was most closely related to Bacillus thermotolerans CCTCC AB 2012108 T by comparison of 16S rRNA gene sequence (97.2% similarity) and to Bacillus wudalianchiensis CCTCC AB 2015266 T by comparison of gyrB gene sequence (80.1% similarity). The draft genome of strain CX253T comprised 3,929,195 bp with a G + C content of 43.3 mol%. The average nucleotide identity and digital DNA-DNA hybridization values between strain CX253T and phylogenetically related Bacillus species were lower than 95% and 70%, respectively. Thus, the polyphasic evidence generated through phenotypic, chemotaxonomic and genomic methods confirmed that strain CX253T (= GDMCC 1.1608 T = KACC 21318 T) was a novel species of the genus Bacillus, for which the name Bacillus aerolatus sp. nov. is proposed.


Assuntos
Aerossóis , Bacillus/classificação , Microbiologia Ambiental , Bacillaceae/genética , Bacillus/genética , Bacillus/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , Ácido Diaminopimélico/análise , Ácidos Graxos/análise , Glicolipídeos/análise , Hibridização de Ácido Nucleico , Fosfolipídeos/análise , Filogenia , RNA Ribossômico 16S/genética , Especificidade da Espécie
8.
Int J Syst Evol Microbiol ; 70(5): 3139-3144, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32375934

RESUMO

A Gram-stain-positive, non-flagellated, non-gliding, coccoid bacterial strain, designated JLT9T, was isolated from the shallow-sea hydrothermal system off Kueishantao Island, Taiwan, ROC. Strain JLT9T was aerobic, chemoheterotrophic and grew optimally at 35 °C, at pH 6.0 and in the presence of 2.5 % (w/v) NaCl. Strain JLT9T exhibited highest 16S rRNA gene sequence similarity to Serinicoccus marinus DSM 15273T (98.83 %). Phylogenetic trees based on 16S rRNA gene sequences revealed that strain JLT9T belonged to the genus Serinicoccus, clustering with Serinicoccus marinus JC1078T, Serinicoccus profundi MCCC 1A05965T, Serinicoccus sediminis GP-T3-3T and Serinicoccus chungangensis CAU9536T. The digital DNA-DNA genome hybridization values between strain JLT9T and the closest related strain S. marinus DSM 15273T was 34.30 %. The DNA G+C content was 72.43 mol%. The dominant fatty acids were identified as iso-C15 : 0 (41.4 %) and iso-C16 : 0 (24.7 %). The polar lipids of strain JLT9T comprised diphosphatidylglycerol, phosphatidylcholine, phosphatidylglycerol, three unidentified glycolipid and an unidentified phospholipid. The predominant isoprenoid quinone was MK-8 (H4). The cell wall contained ornithine and serine, and no diaminopimelic acid. On the basis of phylogenetic data and several distinct phenotypic characteristics, strain JLT9T represents a novel species of the genus Serinicoccus, for which the name Serinicoccus hydrothermalis sp. nov. is proposed. The type strain is JLT9T (=CGMCC 1.15779T=JCM 31502T).


Assuntos
Actinomycetales/classificação , Fontes Hidrotermais/microbiologia , Filogenia , Água do Mar/microbiologia , Actinomycetales/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Glicolipídeos/química , Ilhas , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Taiwan , Vitamina K 2/análogos & derivados , Vitamina K 2/química
9.
Int J Syst Evol Microbiol ; 70(5): 3340-3347, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32375935

RESUMO

A novel Gram-stain-positive, actinobacterial strain, designated C5-26T, was isolated from soil from a natural cave in Jeju, Republic of Korea, and its taxonomic position was investigated using a polyphasic approach. The organism was aerobic, and cells were non-spore-forming, non-motile cocci that occurred singly, in pairs, in triplets, in tetrads, in short chains or in irregular clusters. Colonies of the cells were circular, convex, entire and white. The peptidoglycan type was A4α with an l-Ser-d-Asp interpeptide bridge. The whole-cell sugars comprised glucose, rhamnose, mannose, arabinose, galactose and ribose. The major menaquinone was MK-8(H4). The polar lipids contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and an unidentified phospholipid. The major fatty acids were iso-C16 : 0 and iso-C16 : 1 h. The size of the draft genome was 5.32 Mbp with depth of coverage of 161×. The G+C content of the genomic DNA was 67.1 mol%. Phylogenetic analyses based on 16S rRNA gene sequences showed that the novel isolate belonged to the family Dermacoccaceae and formed a distinct subcluster at the base of the radiation of the genus Luteipulveratus. Highest sequence similarities of the novel isolate were found to the type strains of Luteipulveratus halotolerans (96.2 %), Branchiibius hedensis (95.4 %), Luteipulveratus mongoliensis (95.4 %) and Branchiibius cervicis (95.3 %). The whole genome-based phylogeny supported the novelty of the isolate at the genus level in the family Dermacoccaceae. On the basis of data from this polyphasic study, strain C5-26T (=KCTC 39632T=DSM 108676T) represents a novel species of a new genus in the family Dermacoccaceae, for which the name Leekyejoonella antrihumi gen. nov., sp. nov. is proposed.


Assuntos
Actinobacteria/classificação , Cavernas/microbiologia , Filogenia , Microbiologia do Solo , Actinobacteria/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , DNA Bacteriano/genética , Ácidos Graxos/química , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
10.
Int J Syst Evol Microbiol ; 70(5): 3295-3299, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32375943

RESUMO

A Gram-stain-positive, motile, rod-shaped and endospore-forming strain, SYSU K30002T, was isolated from a soil sample collected from a karst cave in Xingyi county, Guizhou province, south-west China. SYSU K30002T grew at 28-40 °C (optimum, 37 °C), at pH 5.0-8.0 (optimum, pH 7.0) and in the presence of 0-4 % (w/v) NaCl (optimum in the absence of NaCl). The cell-wall peptidoglycan type was A4α (Lys-Asp). The cell-wall sugars of SYSU K30002T were ribose, galactose and mannose, and MK-7 was the menaquinone. The major fatty acids were iso-C15 : 0, C16 : 1 ω7c alcohol and iso-C16 : 0. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and two unidentified phospholipids. The G+C content of the genomic DNA was 36.1 mol%. The average nucleotide identity values between SYSU K30002T and its closest relatives were below the cut-off level (95-96 %) for species delineation. Based on phenotypic, chemotaxonomic and genome comparisons, strain SYSU K30002T represents a novel species of the genus Lysinibacillus, for which the name Lysinibacillusantri sp. nov. is proposed. The type strain is SYSU K30002T (=KCTC 33955T=CGMCC 1.13504T).


Assuntos
Bacillaceae/classificação , Cavernas/microbiologia , Filogenia , Microbiologia do Solo , Bacillaceae/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , China , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/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
11.
Int J Syst Evol Microbiol ; 70(5): 3406-3412, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32375947

RESUMO

A Gram-stain-positive, strictly aerobic and rod-shaped bacterium, designated as 3 H-10T, was isolated from a yellow water sample collected from the manufacturing process of strong flavor Chinese baijiu in Yibin region of Sichuan province (PR China). Oval endospores were formed at the subtermini of cells with swollen sporangia. The isolate was able to grow at temperatures of 20-45 °C (optimum growth at 37 °C), at pH 6.0-10.0 (optimum growth at pH 8.0) and in the presence of 0-2 % (w/v) NaCl (optimum growth with 0 % NaCl). Ribose was the major cell-wall sugar, and meso-diaminopimelic acid (meso-DAP) was the diagnostic amino acid. The main polar lipids of 3 H-10T included diphosphatidylglycerol (DPG), phosphatidylglycerol (PG) and phosphatidylethanolamine (PE). MK-7 was predominant menaquinone and iso-C15 : 0 (60.7 %) was the major fatty acid. Comparisons of 16S rRNA gene sequence indicated that 3 H-10T was most closely related to Bacillus mesophilus SA4T (96.30 %), Bacillus ginsengihumi Gsoil 114T (96.27 %) and Bacillus shackletonii LMG 18435T (96.27 %). The average nucleotide identity (ANI) values between strain 3 H-10T and the three type strains mentioned above were 69.56, 70.19 and 70.67 %, respectively. The genomic DNA G+C content was 35.4 mol%. On the basis of its phenotypic, chemotaxonomic and phylogenetic properties, strain 3 H-10T represents a novel species of the genus Bacillus, for which the name Bacillus aquiflavi sp. nov. is proposed. The type strain is Bacillus aquiflavi 3 H-10T (=CICC 24755T=JCM 33703T).


Assuntos
Bebidas Alcoólicas/microbiologia , Bacillus/classificação , Filogenia , Bacillus/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , China , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Água
12.
Curr Top Microbiol Immunol ; 425: 17-28, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32385534

RESUMO

Dihydroxynaphthalene melanin (DHN-melanin) is an integral component of the conidial cell wall surface, which has a central role in the pathogenicity of the major human airborne fungal pathogen Aspergillus fumigatus. Although the biosynthetic pathway for A. fumigatus DHN-melanin production has been well characterized, the molecular interactions of DHN-melanin with the immune system have been incompletely understood. Recent studies demonstrated that apart from concealing immunostimulatory cell wall polysaccharides, calcium sequestration by DHN-melanin inhibits essential host effector pathways regulating phagosome biogenesis and prevents A. fumigatus conidia killing by phagocytes. From the host perspective, DHN-melanin is specifically recognized by a C-type lectin receptor (MelLeC) present in murine endothelia and in human myeloid cells. Furthermore, DHN-melanin activates platelets and facilitates opsonophagocytosis by macrophages via binding to soluble pattern recognition receptors. Dissecting the dynamics of DHN-melanin organization on the fungal cell wall and the molecular interplay with the immune system will lead to a better understanding of A. fumigatus pathophysiology.


Assuntos
Aspergillus fumigatus , Melaninas , Naftóis , Animais , Aspergilose/imunologia , Aspergilose/metabolismo , Aspergilose/microbiologia , Aspergillus fumigatus/citologia , Aspergillus fumigatus/imunologia , Aspergillus fumigatus/metabolismo , Aspergillus fumigatus/patogenicidade , Parede Celular/química , Parede Celular/metabolismo , Humanos , Lectinas Tipo C/metabolismo , Melaninas/metabolismo , Naftóis/metabolismo , Receptores Mitogênicos/metabolismo
13.
Curr Top Microbiol Immunol ; 425: 331-369, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32418033

RESUMO

The beginning of our understanding of the cell wall construction came from the work of talented biochemists in the 70-80's. Then came the era of sequencing. Paradoxically, the accumulation of fungal genomes complicated rather than solved the mystery of cell wall construction, by revealing the involvement of a much higher number of proteins than originally thought. The situation has become even more complicated since it is now recognized that the cell wall is an organelle whose composition continuously evolves with the changes in the environment or with the age of the fungal cell. The use of new and sophisticated technologies to observe cell wall construction at an almost atomic scale should improve our knowledge of the cell wall construction. This essay will present some of the major and still unresolved questions to understand the fungal cell wall biosynthesis and some of these exciting futurist approaches.


Assuntos
Parede Celular/metabolismo , Fungos/citologia , Fungos/metabolismo , Parede Celular/química
14.
Nat Commun ; 11(1): 2170, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32358503

RESUMO

Plants as non-mobile organisms constantly integrate varying environmental signals to flexibly adapt their growth and development. Local fluctuations in water and nutrient availability, sudden changes in temperature or other abiotic and biotic stresses can trigger changes in the growth of plant organs. Multiple mutually interconnected hormonal signaling cascades act as essential endogenous translators of these exogenous signals in the adaptive responses of plants. Although the molecular backbones of hormone transduction pathways have been identified, the mechanisms underlying their interactions are largely unknown. Here, using genome wide transcriptome profiling we identify an auxin and cytokinin cross-talk component; SYNERGISTIC ON AUXIN AND CYTOKININ 1 (SYAC1), whose expression in roots is strictly dependent on both of these hormonal pathways. We show that SYAC1 is a regulator of secretory pathway, whose enhanced activity interferes with deposition of cell wall components and can fine-tune organ growth and sensitivity to soil pathogens.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Citocininas/metabolismo , Resistência à Doença/genética , Ácidos Indolacéticos/metabolismo , Proteínas de Membrana/metabolismo , Reguladores de Crescimento de Planta/metabolismo , Raízes de Plantas/metabolismo , Transcriptoma/genética , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Parede Celular/química , Parede Celular/metabolismo , Endossomos/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/genética , Complexo de Golgi/metabolismo , Proteínas de Membrana/genética , Raízes de Plantas/microbiologia , Plantas Geneticamente Modificadas/metabolismo , Plasmodioforídeos/patogenicidade , Via Secretória/genética , Solo , Proteínas de Transporte Vesicular/metabolismo
15.
Int J Syst Evol Microbiol ; 70(3): 1993-2002, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32228773

RESUMO

Three isolates, 5K138T, 8K307T and KC603T, with typical morphological characteristics of members of the genus Jiangella were obtained during a study searching for novel actinobacteria with biosynthetic potential from the Karakum Desert. A polyphasic approach was adopted to determine taxonomic affiliations of the strains. The strains showed chemotaxonomic properties consistent with their classification as representing members of the genus Jiangella such as ll-diaminopimelic acid in the cell wall peptidoglycan, diphosphatidylglycerol, phosphatidylglycerol and phosphatidylinositol as major polar lipids as well as MK-9(H4) as a major menaquinone. Pairwise sequence comparisons of the 16S rRNA genes showed that the strains were closely related to Jiangella alba DSM 45237T, Jiangella rhizosphaerae NEAU-YY265T and Jiangella mangrovi 3SM4-07T with higher than 99 % sequence identities. However, a combination of phenotypic and phylogenetic approaches as well as genome-based comparative analyses confirmed the taxonomic positions of these strains as representing distinct species within the genus Jiangella. Therefore, strains 5K138T, 8K307T and KC603T should each be classified as representing a novel species within the genus Jiangella, for which the names Jiangella asiatica sp. nov., Jiangella aurantiaca sp. nov. and Jiangella ureilytica sp. nov. are proposed, respectively. The type strains of the proposed novel species are as follows: Jiangella asiatica 5K138T (=JCM 33518T=CGMCC 4.7672T), Jiangella aurantiaca 8K307T (=JCM 33519T=CGMCC 4.7621T) and Jiangella ureilytica KC603T (=JCM 33520T=CGMCC 4.7618T).


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/química , Ácidos Graxos/química , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Turcomenistão , Vitamina K 2/análogos & derivados , Vitamina K 2/química
16.
Int J Syst Evol Microbiol ; 70(3): 2003-2007, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32234114

RESUMO

A yellow-pigmented, Gram-stain-negative, aerobic, non-motile rod shaped, mesophilic bacterium, designated strain N7XX-4T, was isolated from cattail root grown on the mine tailings of Phoenix mountain, Tongling city, Anhui Province (PR China). Analysis of the 16S rRNA gene sequence revealed that the strain represented a novel member of the family Microbacteriaceae. The nearest phylogenetic neighbour was Lysinimonas kribbensis MSL-13T (97.8 % 16S rRNA gene sequence similarity). The most abundant fatty acid in whole cells of N7XX-4T was anteiso-C15 : 0 (29.9 %). The predominant menaquinones were MK-12(H2), MK-13(H2) and MK-11(H2). The peptidoglycan type of the isolate was B1δ with l-Lys as the diagnostic cell-wall diamino acid. On the basis of differences in phenotypic and genotypic characteristics, strain N7XX-4T (=CGMCC 1.16548T=DSM 106791T=JCM 32630T) is designated as the type strain of a novel species of the genus Lysinimonas, for which the name Lysinimonas yzui sp. nov. is proposed.


Assuntos
Actinobacteria/classificação , Mineração , Filogenia , Microbiologia do Solo , Typhaceae/microbiologia , Actinobacteria/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , China , DNA Bacteriano/genética , Ácidos Graxos/química , Peptidoglicano/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/química
17.
Int J Syst Evol Microbiol ; 70(5): 3069-3075, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32223833

RESUMO

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


Assuntos
Sedimentos Geológicos/microbiologia , Micromonospora/classificação , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Japão , Micromonospora/isolamento & purificação , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Água do Mar/microbiologia , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados
18.
Arch Microbiol ; 202(6): 1545-1549, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32246163

RESUMO

A bacterial strain, designated YIM 98839T, was isolated from the hypersaline sediment of Aiding Lake in Xinjiang province, North-West China. The strain was Gram-stain-positive, motile, aerobic, produced oval subterminal or central endospores in swollen sporangia. The whole-cell hydrolysates contain meso-diaminopimelic acid as the diagnostic cell-wall diamino acid. Galactose, fucose and ribose are the major whole-cell sugars. The phospholipids are diphosphatidylglycerol, phosphatidylglycerol and one unknown phospholipid. The predominant menaquinone is MK-7. The major fatty acids are anteiso-C15:0, anteiso-C17:0 and iso-C15:0. The DNA G + C content of the type strain is 37.0 mol%. Phylogenetic analysis indicated that the isolate belongs to the genus Oceanobacillus. However, it differed from its closest relative, Oceanobacillus limi H9BT in many physiological characteristics. Moreover, the DNA-DNA relatedness values between the novel isolate and the relative type strain was 20.2%. Based on comparative analysis of polyphasic taxonomic data, strain YIM 98839T represents a novel species of the genus Oceanobacillus, for which the name Oceanobacillus halotolerans sp. nov. is proposed. The type strain is YIM 98839T (= CGMCC 1.17002T = KCTC 43140T).


Assuntos
Bacillaceae/classificação , Bacillaceae/genética , Bacillaceae/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases/genética , Parede Celular/química , China , DNA Bacteriano/genética , Ácido Diaminopimélico/análise , Ácidos Graxos/análise , Lagos/microbiologia , Fosfolipídeos/análise , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
19.
Int J Syst Evol Microbiol ; 70(5): 3027-3036, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32223834

RESUMO

A pink-coloured bacterium (strain KR32T) was isolated from cheese and assigned to the 'Arthrobacter agilis group'. Members of the 'pink Arthrobacter agilis group' form a stable clade (100 % bootstrap value) and contain the species Arthrobacter agilis, Arthrobacter ruber and Arthrobacter echini, which share ≥99.0 % 16S rRNA gene sequence similarity. Isolate KR32T showed highest 16S rRNA gene sequence similarity (99.9 %) to A. agilis DSM 20550T. Additional multilocus sequence comparison confirmed the assignment of strain KR32T to the clade 'pink A. agilis group'. Average nucleotide identity and digital DNA-DNA hybridization values between isolate KR32T and A. agilis DSM 20550T were 82.85 and 26.30 %, respectively. The G+C content of the genomic DNA of isolate KR32T was 69.14 mol%. Chemotaxonomic analysis determined anteiso-C15 : 0 as the predominant fatty acid and MK-9(H2) as the predominant menaquinone. Polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and monoacyldimannosyl-monoacylglycerol. The peptidoglycan type of the isolate was A3α. The carotenoid bacterioruberin was detected as the major pigment. At 10 °C, strain KR32T grew with increased concentrations of bacterioruberin and production of unsaturated fatty acids. Strain KR32T was a Gram-stain-positive, catalase-positive, oxidase-positive and coccus-shaped bacterium with optimal growth at 27-30 °C and pH 8. The results of phylogenetic and phenotypic analyses enabled the differentiation of the isolate from other closely related species of the 'pink A. agilis group'. Therefore, strain KR32T represents a novel species for which the name Arthrobacter bussei sp. nov. is proposed. The type strain is KR32T (=DSM 109896T=LMG 31480T=NCCB 100733T).


Assuntos
Arthrobacter/classificação , Queijo/microbiologia , Microbiologia de Alimentos , Filogenia , Animais , Arthrobacter/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Bovinos , Parede Celular/química , DNA Bacteriano/genética , Ácidos Graxos/química , Feminino , Alemanha , Glicolipídeos/química , Leite , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
20.
Food Chem ; 321: 126707, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32244134

RESUMO

Mealiness is one of the most important textural failure of apple fruit and four patterns of mealiness involving five apple cultivars were identified as the rapid, moderate, slow and none, requiring 3, 7, 14, 49 days at 25 °C, respectively. In comparison with the non-mealy 'Fuji' apple, parenchyma cells of mealy apples became detached and remained intact. Highly methyl-esterified homogalacturonan was strongly immunolabeled in the cell wall of slow and non-mealy apples. The mobility of water was enhanced in the cell wall during mealiness. Principal components analysis of FTIR spectra discriminated the cell wall materials (CWM) based on the mealiness progress. Heavy loss of CWM and its water-insoluble fractions but limited increase of water-soluble fractions, and the increase of crystalline micelles of CWM were closely associated with the mealiness progress. Overall, the occurrence of mealiness might attribute to structural, physical and biochemical modifications of CWM during tissue senescence.


Assuntos
Parede Celular/química , Malus/química , Pectinas/química , Frutas/química , Refeições
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