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1.
Artigo em Inglês | MEDLINE | ID: mdl-34047689

RESUMO

A novel Gram-stain-negative, rod-shaped, non-motile, yellowish bacterium, designated strain 1.3611T, was isolated from the wormcast of Eisenia foetida. The strain grew optimally at 30-37 ℃, at pH 7.0 and with 0-1.0 % (w/v) NaCl. Based on the results of 16S rRNA gene sequence and phylogenetic analyses, strain 1.3611T showed the highest degree of 16S rRNA gene sequence similarity to Sphingobacterium olei HAL-9T (97.0 %), followed by Sphingobacterium alkalisoli Y3L14T (95.8 %). The respiratory quinone of strain 1.3611T was menaquinone-7 (MK-7) and its major cellular fatty acids were iso-C15 : 0 (41.3 %), summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c, 22.1 %) and iso-C17 : 0 3-OH (16.2 %). The major polar lipids were sphingophospholipid, phosphatidylethanolamine, four unidentified glycolipids, two unidentified phospholipids and five unidentified polar lipids. The genomic DNA G+C content was 39.0 mol%. The digital DNA-DNA hybridization and average nucleotide identity values between the genomes of strain 1.3611T and S. olei HAL-9T were 37.9 and 88.9 %, respectively. According to the phenotypic and chemotaxonomic phylogenetic results, strain 1.3611T should represent a novel species of the genus Sphingobacterium, for which the name Sphingobacterium lumbrici sp. nov. is proposed, with strain 1.3611T (=KCTC 62980T=CCTCC AB 2018349T) as the type strain.


Assuntos
Oligoquetos/microbiologia , Filogenia , Sphingobacterium/classificação , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Hibridização de Ácido Nucleico , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Sphingobacterium/isolamento & purificação , Vitamina K 2/análogos & derivados , Vitamina K 2/química
2.
Artigo em Inglês | MEDLINE | ID: mdl-33881980

RESUMO

A polyphasic study was undertaken to determine the taxonomic position of two halophilic archaeal strains, TH32T and YPL4T, isolated from saline soil and a salt mine in PR China, respectively. Strains TH32T and YPL4T both have two dissimilar 16S rRNA genes. The two strains exhibited sequence similarities of 91.5-95.5 % for 16S rRNA genes and 90.9 % for the rpoB' gene. Sequence similarities of 16S rRNA genes and the rpoB' gene between the two strains and the current four members of Halosimplex were 90.6-97.4 % and 91.4-93.5 %, respectively. Phylogenetic analysis revealed that the two strains formed different branches separating them from the current Halosimplex members. Several phenotypic characteristics differentiate strains TH32T and YPL4T from current Halosimplex members. The polar lipids of the two strains are phosphatidic acid, phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and four glycolipids. Two of the glycolipids are chromatographically identical to disulfated mannosyl glucosyl diether and sulfated mannosyl glucosyl diether, respectively, and the remaining two glycolipids are unidentified. The average nucleotide identity (ANI) and in silico DNA-DNA hybridization (DDH) values between the two strains and the current members of Halosimplex (ANI 80.4-89.2 % and in silico DDH 24.0-41.8 %) were much lower than the threshold values proposed as a species boundary, suggesting that the two strains represent novel species of Halosimplex. The values between the two strains (ANI 81.3 % and in silico DDH 24.9 %) were also much lower than the recommended threshold values, which revealed that the two strains represent two genomically different species of Halosimplex. These results showed that strains TH32T (=CGMCC 1.15190T=JCM 30840T) and YPL4T (=CGMCC 1.15329T=JCM 31108T) represent two novel species of Halosimplex, for which the names Halosimplex halophilum sp. nov. and Halosimplex salinum sp. nov. are proposed.


Assuntos
Halobacteriaceae/classificação , Mineração , Filogenia , Microbiologia do Solo , Composição de Bases , DNA Arqueal/genética , Glicolipídeos/química , Halobacteriaceae/isolamento & purificação , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Cloreto de Sódio
3.
Artigo em Inglês | MEDLINE | ID: mdl-33906707

RESUMO

An anaerobic, Gram-stain-positive, rod-shaped, motile and spore-forming bacterium, designated strain LBM18003T, was isolated from pit clay used for making Chinese strong aroma-type liquor. Growth occurred at 20-40 °C (optimum, 30-37 °C), pH 4.5-9.5 (optimum, pH 6.5-7.0) and in the presence of 0.0-1.0 % (w/v) sodium chloride (optimum, 0 %). The predominant fatty acids were C16:0, C14:0, C14:0 DMA and C16:0 3-OH, and the major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, two unidentified phospholipids and nine unidentified glycolipids. Phylogenetic analysis revealed that strain LBM18003T is a novel member of the family Oscillospiraceae. The 16S rRNA gene sequence similarities of strain LBM18003T to its two most closely related species were less than 94.5 % for distinguishing genera, i.e. closely related to Caproiciproducens galactitolivorans JCM 30532T (94.1 %) and Caproicibacter fermentans DSM 107079T (93.2 %). The genome size of strain LBM18003T was 2 996 201 bp and its DNA G+C content was 48.48 mol%. Strain LBM18003T exhibited 67.8 and 68.1% pairwise-determined whole-genome average nucleotide identity values to Caproiciproducens galactitolivorans JCM 30532T and Caproicibacter fermentans DSM 107079T, respectively; and showed 62.2 and 61.0 % the average amino acid identity values to Caproiciproducens galactitolivorans JCM 30532T and Caproicibacter fermentans DSM 107079T, respectively; and demonstrated 46.1 and 41.5 % conserved genes to Caproiciproducens galactitolivorans JCM 30532T and Caproicibacter fermentans DSM 107079T, respectively. The comparisons of 16S rRNA gene and genome sequences confirmed that strain LBM18003T represented a novel genus of the family Oscillospiraceae. Based on morphological, physiological, biochemical, chemotaxonomic, genotypic and phylogenetic results, strain LBM18003T represents a novel species of a novel genus of the family Oscillospiraceae, for which the name Caproicibacterium amylolyticum gen. nov., sp. nov. is proposed. The type strain is LBM18003T (=GDMCC 1.1626T=JCM 33783T).


Assuntos
Argila , Clostridiales/classificação , Filogenia , Bebidas Alcoólicas , Técnicas de Tipagem Bacteriana , Composição de Bases , China , Clostridiales/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Odorantes , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
4.
Artigo em Inglês | MEDLINE | ID: mdl-33909547

RESUMO

A Gram-stain-positive, strictly aerobic, spore-forming, rod-shaped and non-motile bacterium designated strain SIJ1T was obtained from tidal flat sediment collected from the northern shore of Kuwait Bay, northwest of the Arabian Gulf. Strain SIJ1T grew optimally at 30 °C and pH 7-8 in the presence of 6 % (w/v) NaCl. The cell-wall peptidoglycan was based on meso-diaminopimelic acid and an unsaturated menaquinone with seven isoprene units (MK-7) was the predominant respiratory quinone. It contained anteiso-C15 : 0, iso-C16 : 0 and iso-C15 : 0 as the major fatty acids and ribose as the major whole-cell sugar. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, unidentified phospholipid, an unidentified glycolipid, phosphoglycolipid and an unidentified lipid. Phylogenetic analysis based on 16S rRNA genes revealed that SIJ1T showed a distinct evolutionary lineage within the Firmicutes. The DNA G+C content was 43.1 mol% and the full genome analysis for strain SIJ1T showed that it had a genome size of 3 989 945 bp and contained 4085 predicted protein-encoding genes. The SIJ1T annotated genome showed more stress resistance encoding genes in comparison to its closely related strains. The amino acid identity and average nucleotide identity data for the whole genome proved that strain SIJ1T does indeed represent a novel genus. The strain was distinguishable from the phylogenetically related genera through differences in several phenotypic properties. On the basis of the phenotypic, phylogenetic and genetic data, strain SIJ1T represents a novel genus and species in the family Bacillaceae, for which the name Litoribacterium kuwaitense gen. nov., sp. nov. is proposed. The type strain is SIJ1T (=DSM 28862T=LMG 28316T).


Assuntos
Sedimentos Geológicos/microbiologia , Filogenia , Água do Mar/microbiologia , Bacillaceae/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Baías , Parede Celular/química , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Glicolipídeos/química , Kuweit , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
5.
Nutrients ; 13(3)2021 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-33810073

RESUMO

Breast milk is an unbeatable food that covers all the nutritional requirements of an infant in its different stages of growth up to six months after birth. In addition, breastfeeding benefits both maternal and child health. Increasing knowledge has been acquired regarding the composition of breast milk. Epidemiological studies and epigenetics allow us to understand the possible lifelong effects of breastfeeding. In this review we have compiled some of the components with clear functional activity that are present in human milk and the processes through which they promote infant development and maturation as well as modulate immunity. Milk fat globule membrane, proteins, oligosaccharides, growth factors, milk exosomes, or microorganisms are functional components to use in infant formulas, any other food products, nutritional supplements, nutraceuticals, or even for the development of new clinical therapies. The clinical evaluation of these compounds and their commercial exploitation are limited by the difficulty of isolating and producing them on an adequate scale. In this work we focus on the compounds produced using milk components from other species such as bovine, transgenic cattle capable of expressing components of human breast milk or microbial culture engineering.


Assuntos
Desenvolvimento Infantil , Fenômenos Fisiológicos da Nutrição do Lactente , Proteínas do Leite/química , Proteínas do Leite/imunologia , Leite Humano/química , Leite Humano/imunologia , Feminino , Glicolipídeos/química , Glicolipídeos/imunologia , Glicolipídeos/metabolismo , Glicoproteínas/química , Glicoproteínas/imunologia , Glicoproteínas/metabolismo , Humanos , Lactente , Recém-Nascido , Gotículas Lipídicas/química , Gotículas Lipídicas/imunologia , Gotículas Lipídicas/metabolismo , Proteínas do Leite/metabolismo , Leite Humano/metabolismo
6.
Artigo em Inglês | MEDLINE | ID: mdl-33913805

RESUMO

Two bacterial strains, FWR-8T and CFWR-9T, were isolated from the gut of larvae of Protaetia brevitarsis seulensis that were raised at the National Institute of Agricultural Sciences, Wanju-gun, Republic of Korea. Both strains were strictly aerobic, Gram-stain-positive and non-motile. Strain FWR-8T possessed the highest sequence similarity (98.7 %) to that of Protaetiibacter intestinalis 2DFWR-13T and the phylogenetic tree revealed that strain FWR-8T formed a cluster with Ptb. intestinalis 2DFWR-13T. Pseudolysinimonas kribbensis MSL-13T and Lysinimonas yzui N7XX-4T shared a high 16S rRNA gene sequence similarity (97.8 %) and formed a cluster adjacent to the cluster that included Ptb. intestinalis 2DFWR-13T. The 16S rRNA gene sequence of strain CFWR-9T exhibited the highest similarity (97.7 %) to that of Agromyces binzhouensis OAct353T and the phylogenetic tree indicated that strain CFWR-9T formed one independent cluster with A. binzhouensis OAct353T that was within the radius of the genus Agromyces. The peptidoglycan type, major fatty acids, major menaquinones and total polar lipids of strain FWR-8T were characterized as type B1, iso-C16 : 0, anteiso-C15 : 0 and anteiso-C17 : 0, MK-15, MK-16 and MK-14, and diphosphatidylglycerol, phosphatidylglycerol, two unidentified glycolipids and one unidentified lipid, respectively. Those from strain CFWR-9T were type B1, iso-C16 : 0, anteiso-C15 : 0 and anteiso-C17 : 0, MK-11, MK-12 and MK-10, and diphosphatidylglycerol, phosphatidylglycerol, two unidentified glycolipids and one unidentified lipid, respectively. Based on the phenotypic and genotypic data, strains FWR-8T and CFWR-9T each represent a novel species within the genera Protaetiibacter and Agromyces, respectively. For these species, the names Protaetiibacter larvae sp. nov. and Agromyces intestinalis sp. nov. have been proposed, with the type strains FWR-8T (=KACC 19322T=NBRC 113051T) and CFWR-9T (=KACC 19306T=NBRC 113046T), respectively. Our results also justify a reclassification of Lysinimonas yzui as Pseudolysinimonas yzui comb. nov. and an emended description of the genus Pseudolysinimonas isprovided.


Assuntos
Actinobacteria/classificação , Besouros/microbiologia , Trato Gastrointestinal/microbiologia , Filogenia , Actinobacteria/isolamento & purificação , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Larva/microbiologia , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Vitamina K 2/química
7.
Int J Nanomedicine ; 16: 925-939, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33603360

RESUMO

Background: Antimicrobial resistance poses substantial risks to human health. Thus, there is an urgent need for novel antimicrobial agents, including alternative compounds, such as peptides derived from bacterial toxin-antitoxin (TA) systems. ParELC3 is a synthetic peptide derived from the ParE toxin reported to be a good inhibitor of bacterial topoisomerases and is therefore a potential antibacterial agent. However, ParELC3 is inactive against bacteria due to its inability to cross the bacterial membranes. To circumvent this limitation we prepared and used rhamnolipid-based liposomes to carry and facilitate the passage of ParELC3 through the bacterial membrane to reach its intracellular target - the topoisomerases. Methods and Results: Small unilamellar liposome vesicles were prepared by sonication from three formulations that included 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine and cholesterol. ParELC3 was loaded with high efficiency into the liposomes. Characterization by DLS and TEM revealed the appropriate size, zeta potential, polydispersity index, and morphology. In vitro microbiological experiments showed that ParELC3 loaded-liposomes are more efficient (29 to 11 µmol·L-1) compared to the free peptide (>100 µmol·L-1) at inhibiting the growth of standard E. coli and S. aureus strains. RL liposomes showed high hemolytic activity but when prepared with POPC and Chol this activity had a significant reduction. Independently of the formulation, the vesicles had no detectable cytotoxicity to HepG2 cells, even at the highest concentrations tested (1.3 mmol·L-1 and 50 µmol·L-1 for rhamnolipid and ParELC3, respectively). Conclusion: The present findings suggest the potential use of rhamnolipid-based liposomes as nanocarrier systems to enhance the bioactivity of peptides.


Assuntos
Antibacterianos/farmacologia , Portadores de Fármacos/química , Glicolipídeos/química , Nanopartículas/química , Peptídeos/farmacologia , Sistemas Toxina-Antitoxina , Sequência de Aminoácidos , Permeabilidade da Membrana Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Difusão Dinâmica da Luz , Escherichia coli/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Células Hep G2 , Humanos , Hidrodinâmica , Lipossomos , Testes de Sensibilidade Microbiana , Peptídeos/química , Sonicação , Staphylococcus aureus/efeitos dos fármacos
8.
Nat Commun ; 12(1): 1201, 2021 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-33619275

RESUMO

Glycolipids are complex glycoconjugates composed of a glycan headgroup and a lipid moiety. Their modular biosynthesis creates a vast amount of diverse and often isomeric structures, which fulfill highly specific biological functions. To date, no gold-standard analytical technique can provide a comprehensive structural elucidation of complex glycolipids, and insufficient tools for isomer distinction can lead to wrong assignments. Herein we use cryogenic gas-phase infrared spectroscopy to systematically investigate different kinds of isomerism in immunologically relevant glycolipids. We show that all structural features, including isomeric glycan headgroups, anomeric configurations and different lipid moieties, can be unambiguously resolved by diagnostic spectroscopic fingerprints in a narrow spectral range. The results allow for the characterization of isomeric glycolipid mixtures and biological applications.


Assuntos
Temperatura Baixa , Glicolipídeos/química , Galactosilceramidas/química , Monossacarídeos/análise , Espectrofotometria Infravermelho , Esfingosina/química , Estereoisomerismo
9.
Artigo em Inglês | MEDLINE | ID: mdl-33480836

RESUMO

A bacterial strain, designated TRM 80801T, was isolated from the Karelinea in Taklamakan desert, Xinjiang Uygur Autonomous Region, north-west China. Cells were Gram-stain-positive, aerobic, non-motile, short rods. Strain TRM 80801T grew at 4-50 °C, with optimum growth at 28 °C, and grew at pH 6.0-11.0 and 1-15 % (w/v) NaCl. Phylogenetic analyses of the 16S rRNA gene sequences placed strain TRM 80801T within the genus Microbacterium with the highest similarities to Microbacterium suaedae YZYP 306T (98.97 %) and Microbacterium indicum BBH6T (98.17 %), respectively. The DNA G+C content of TRM 80801T is 69.38 mol%. The cell-wall peptidoglycan contained the amino acids ornithine, glutamic acid, glycine and alanine, the diagnostic diamino acid was ornithine. The acyl type of the peptidoglycan was glycolyl. Whole-cell sugars were ribose, mannose, glucose, rhamnose and galactose. The major cellular fatty acids were anteiso-C15 : 0, anteiso-C17 : 0 and iso-C16 : 0. The predominant menaquinones were MK-10, MK-11 and MK-12. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol. The whole-genome average nucleotide identity (ANI) value between strain TRM 80801T and Microbacterium suaedae YZYP 306T is 70.2 %. On the basis of the evidence presented in this study, strain TRM 80801T is representative of a novel species in the genus Microbacterium, for which the name Microbacterium karelineae sp. nov. is proposed. The type strain is TRM 80801T (=CCTCC AB 2019248T=KCTC 49357T).


Assuntos
Clima Desértico , Microbacterium/classificação , Filogenia , Plantas Tolerantes a Sal/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Microbacterium/isolamento & purificação , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/química
10.
Arch Biochem Biophys ; 699: 108764, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33460582

RESUMO

The interaction of a dirhamnolipid biosurfactant secreted by Pseudomonas aeruginosa with calcium ATPase from sarcoplasmic reticulum (SR) was studied by means of different approaches, such as enzyme activity, fluorescence spectroscopy, Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and molecular docking simulations. The ATP hydrolysis activity was fully inhibited by incubation with dirhamnolipid (diRL) up to 0.1 mM concentration, corresponding to a surfactant concentration below membrane solubilization threshold. Surfactant-protein interaction induced conformational changes in the protein observed by an increase in the accessibility of tryptophan residues to the aqueous phase and by changes in the secondary structure of the protein as seen by fluorescence and FTIR spectroscopy. As a consequence, the protein become more unstable and denatured at lower temperatures, as seen by enzyme activity and DSC studies. Finally, these results were explained at molecular level throughout molecular docking simulations. It is concluded that there is a specific dirhamnolipid-protein interaction not related to the surface activity of the surfactant but to the particular physicochemical properties of the biosurfactant molecule.


Assuntos
Glicolipídeos/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Tensoativos/metabolismo , Animais , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Glicolipídeos/química , Simulação de Acoplamento Molecular , Ligação Proteica , Estrutura Secundária de Proteína/efeitos dos fármacos , Pseudomonas aeruginosa/química , Coelhos , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/antagonistas & inibidores , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/química , Tensoativos/química
11.
Biochemistry ; 60(5): 381-397, 2021 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-33491458

RESUMO

Polyacylated trehaloses in Mycobacterium tuberculosis play important roles in pathogenesis and structural roles in the cell envelope, promoting the intracellular survival of the bacterium, and are potential targets for drug development. Herein, we describe a linear ion-trap multiple-stage mass spectrometric approach (LIT MSn) with high-resolution mass spectrometry to the structural characterization of a glycolipid family that includes a 2,3-diacyltrehalose, 2,3,6-triacyltrehalose, 2,3,6,2',4'-petaacyltrehalose, and a novel 2,3,6,2'-tetraacyltrehalose (TetraAT) subfamily isolated from biofilm cultures of M. tuberculosis H37Rv. The LIT MSn spectra (n = 2, 3, or 4) provide structural information to unveil the location of the palmitoyl/stearoyl and one to four multiple methyl-branched fatty acyl substituents attached to the trehalose backbone, leading to the identification of hundreds of glycolipid species with many isomeric structures. We identified a new TetraAT subfamily whose structure has not been previously defined. We also developed a strategy for defining the structures of the multiple methyl-branched fatty acid substituents, leading to the identification of mycosanoic acid, mycolipenic acid, mycolipodienoic acid, mycolipanolic acid, and a new cyclopropyl-containing acid. The observation of the new TetraAT family, and the realization of the structural similarity between the various subfamilies, may have significant implications in the biosynthetic pathways of this glycolipid family.


Assuntos
Mycobacterium tuberculosis/química , Mycobacterium tuberculosis/enzimologia , Trealose/química , Biofilmes , Parede Celular/química , Ácidos Graxos/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Glicolipídeos/química , Mycobacterium tuberculosis/metabolismo , Isoformas de Proteínas/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Trealose/metabolismo
12.
Food Funct ; 12(4): 1783-1802, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33514994

RESUMO

The behavior of fat globules during the gastric digestion of raw and pasteurized cow, goat, and sheep whole milks was studied using a human gastric simulator. Microstructural and physicochemical analysis revealed that, initially, the coagulation of the milks in the human gastric simulator resulted in the majority of the milk fat globules being entrapped within the curd. As the digestion progressed, the proportion of fat globules entrapped within the aggregated protein matrix (curd) decreased; there was also some flocculation as well as coalescence of the fat globules within the curd. The liberation of the entrapped fat globules from the curd to the liquid phase of the chyme was strongly dependent on the disintegration and hydrolysis of the structured casein network. Surprisingly, the fat globules released (or already present) into the liquid phase of the chyme were not as extensively coalesced as those remaining within the curd. These phenomena were observed to be similar for the raw and pasteurized whole milk of all species. The pasteurized whole milks from all species formed relatively less structured coagula compared with their raw milk counterparts, leading to a greater extent of protein breakdown and, thus, higher proportions of fat release from the pasteurized milk curds. This study provides a deeper understanding of how the curd-forming properties of different mammalian milks in the gastric environment provide controlled delivery of nutrients (such as protein and fat).


Assuntos
Digestão/fisiologia , Glicolipídeos , Glicoproteínas , Gotículas Lipídicas , Leite , Estômago/fisiologia , Animais , Bovinos , Glicolipídeos/análise , Glicolipídeos/química , Glicolipídeos/metabolismo , Glicoproteínas/análise , Glicoproteínas/química , Glicoproteínas/metabolismo , Cabras , Cinética , Gotículas Lipídicas/química , Gotículas Lipídicas/metabolismo , Leite/química , Leite/metabolismo , Ovinos , Fatores de Tempo
13.
J Oleo Sci ; 70(2): 165-173, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33455999

RESUMO

The lipid products that consist of structured lipids rich in palmitic acid (16:0) at the sn-2 position of triacylglycerol (TAG) and rich in low-unsaturated fatty acids (FAs) (LUFAs), such as oleic acid; 18:1 and linoleic acid; 18:2 at the sn-1(3) positions, are useful intermediates for manufacturing human milk fat substitute (HMFS), which contains functional lipid components. In this study, the HMFS intermediate (HMFS-IM) was enzymatically prepared from palm oil without using other oil sources. First, the amount of 16:0 at the sn-2 position of TAG substrate was enhanced from 18.9% to more 34.5% via a random esterification reaction using a non-stereospecific lipase, Novozym® 435, to produce a random-palm substrate. Consequently, 2-monoacylglycerol (2-MAG) rich in 16:0 at the sn-2 position over 88%, together with the FA ethyl ester substrates rich in LUFAs, such as 18:1-Et and 18:2-Et above 93.5% was prepared through ethanolysis reaction using the same lipase from the random-palm substrate and by purification with urea complexation, respectively. As the preferred modified method, a continuous use of the same lipase to these reactions were achieved while reducing the usage of enzyme to half. Finally, an HMFS-IM rich in 16:0 at the sn-2 position more than 60% and LUFA at sn-1(3) positions was prepared using these palm oil-based products, including random-palm, palm-Et, and 2-MAG, via the interesterification reaction using a 1,3-stereospecific lipase, Lipozyme® RM-IM. Thus, HMFS-IM was successfully prepared by palm oil materials with a 65 wt% usage ratio. The concept described in this study will be useful for HMFS manufacturing from a single natural oil substrate, which is not initially rich in 16:0 at the sn-2 position.


Assuntos
Ácidos Graxos Insaturados/química , Glicolipídeos/química , Glicoproteínas/química , Gotículas Lipídicas/química , Substitutos do Leite/síntese química , Leite Humano/química , Óleo de Palmeira/química , Ácido Palmítico/química , Esterificação , Ácido Linoleico/química , Lipase/química , Ácido Oleico/química , Triglicerídeos/química
14.
J Agric Food Chem ; 69(1): 159-169, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33382265

RESUMO

The particle size and fatty acid release of droplets covered with milk fat globule membrane phospholipids with different particle sizes (large/MPL-L; medium/MPL-M; and small/MPL-S) and emulsions with different sources (droplets covered with MPL/MPLs; human milk/HM; and infant formula/IF) were investigated using an infant digestion model. During digestion, droplets exhibited different degrees of aggregation, and the order of the particle size was MPL-L > MPL-M > MPL-S. MPL-M and MPL-S were significantly higher than MPL-L in the release of free fatty acids. No significant difference was observed in the FFA release rate between MPLs and HM. However, the rate was significantly higher than that of IF in the intestinal stage. Compared to IF, a higher content of long-chain polyunsaturated fatty acids and a lower content of saturated fatty acid were observed in MPLs and HM.


Assuntos
Ácidos Graxos/química , Ácidos Graxos/metabolismo , Fosfolipídeos/química , Digestão , Glicolipídeos/química , Glicolipídeos/metabolismo , Glicoproteínas/química , Glicoproteínas/metabolismo , Humanos , Lactente , Fórmulas Infantis/química , Gotículas Lipídicas/química , Gotículas Lipídicas/metabolismo , Leite Humano/química , Leite Humano/metabolismo , Tamanho da Partícula , Fosfolipídeos/metabolismo
15.
Carbohydr Polym ; 254: 117433, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33357906

RESUMO

Driven by the need to find alternatives to control Staphylococcus aureus infections, this work describes the development of chitosan-based particulate systems as carriers for antimicrobial glycolipids. By using a simple ionic gelation method stable nanoparticles were obtained showing an encapsulation efficiency of 41.1 ± 8.8 % and 74.2 ± 1.3 % and an average size of 210.0 ± 15.7 nm and 329.6 ± 8.0 nm for sophorolipids and rhamnolipids chitosan-nanoparticles, respectively. Glycolipids incorporation and particle size was correspondingly corroborated by FTIR-ATR and TEM analysis. Rhamnolipids chitosan nanoparticles (RLs-CSp) presented the highest antimicrobial effect towards S. aureus (ATCC 25923) exhibiting a minimal inhibitory concentration of 130 µg/mL and a biofilm inhibition ability of 99 %. Additionally, RLs-CSp did not interfere with human dermal fibroblasts (AG22719) viability and proliferation under the tested conditions. The results revealed that the RLs-CSp were able to inhibit bacterial growth showing adequate cytocompatibility and might become, after additional studies, a valuable approach to prevent S. aureus related infections.


Assuntos
Antibacterianos/química , Quitosana/química , Portadores de Fármacos , Glicolipídeos/química , Ácidos Oleicos/química , Staphylococcus aureus/efeitos dos fármacos , Tensoativos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Glicolipídeos/isolamento & purificação , Glicolipídeos/farmacologia , Humanos , Testes de Sensibilidade Microbiana , Nanopartículas/química , Nanopartículas/ultraestrutura , Ácidos Oleicos/isolamento & purificação , Ácidos Oleicos/farmacologia , Tamanho da Partícula , Staphylococcus aureus/crescimento & desenvolvimento , Tensoativos/isolamento & purificação , Tensoativos/farmacologia
16.
Artigo em Inglês | MEDLINE | ID: mdl-33351741

RESUMO

A prosthecate bacterial strain, designated G-192T, was isolated from decaying biomass of a haloalkaliphilic cyanobacterium Geitlerinema sp. Z-T0701. The cells were aerobic, Gram-negative, non-endospore-forming and dimorphic, occurring either as sessile bacteria with a characteristic stalk or as motile flagellated cells. The strain utilized a limited range of substrates, mostly peptonaceous, but was able to degrade whole proteins. Growth occurred at 5-46 °C (optimum, 35-40 °C), pH 7.3-10.3 (optimum, pH 8.0-9.0), 0-14 % NaCl (v/w; optimum, 2.0-6.0 %, v/w). The G+C content of the genomic DNA of strain G-192T was 66.8%. Phylogenetic analysis of the 16S rRNA gene sequence revealed that strain G-192T formed a distinct evolutionary lineage within the family Hyphomonadaceae. Strain G-192T showed the highest 16S rRNA sequence similarity to Glycocaulis profundi ZYF765T (95.2%), Oceanicaulis stylophorae GISW-4T (94.2%) and Marinicauda salina WD6-1T (95.5%). The major cellular fatty acids (>5% of the total) were C18:1 ω9c, C18:0 and 11-methyl-C18:1 ω7c. The major polar lipids were glycolipids and phospholipids. The only respiratory quinone was ubiquinone-10 (Q-10). Based on polyphasic results including phylogenomic data, the novel strain could be distinguished from other genera, which suggests that strain G-192T represents a novel species of a new genus, for which the name Alkalicaulis satelles gen. nov., sp. nov. is proposed. The type strain is G-192T (=VKM B-3306T=KCTC 72746T). The strain is the first representative of the stalked bacteria associated with a haloalkaliphilic cyanobacterium. Based on phylogenomic indices and phenotypic data, it is proposed to evolve two novel families Maricaulaceae fam. nov. and Robiginitomaculaceae fam. nov. out of the current family Hyphomonadaceae. In addition, it is proposed to place the first two families in the novel order Maricaulales ord. nov. and novel order Hyphomonadales ord. nov. is proposed to accommodate the family Hyphomonadaceae.


Assuntos
Alphaproteobacteria/classificação , Filogenia , Alphaproteobacteria/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Cianobactérias , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Laboratórios , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/análogos & derivados , Ubiquinona/química
17.
Molecules ; 26(1)2020 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-33374771

RESUMO

The hemibiotrophic fungus Zymoseptoria tritici, responsible for Septoria tritici blotch, is currently the most devastating foliar disease on wheat crops worldwide. Here, we explored, for the first time, the ability of rhamnolipids (RLs) to control this pathogen, using a total of 19 RLs, including a natural RL mixture produced by Pseudomonas aeruginosa and 18 bioinspired RLs synthesized using green chemistry, as well as two related compounds (lauric acid and dodecanol). These compounds were assessed for in vitro antifungal effect, in planta defence elicitation (peroxidase and catalase enzyme activities), and protection efficacy on the wheat-Z. tritici pathosystem. Interestingly, a structure-activity relationship analysis revealed that synthetic RLs with a 12 carbon fatty acid tail were the most effective for all examined biological activities. This highlights the importance of the C12 chain in the bioactivity of RLs, likely by acting on the plasma membranes of both wheat and Z. tritici cells. The efficacy of the most active compound Rh-Est-C12 was 20-fold lower in planta than in vitro; an optimization of the formulation is thus required to increase its effectiveness. No Z. tritici strain-dependent activity was scored for Rh-Est-C12 that exhibited similar antifungal activity levels towards strains differing in their resistance patterns to demethylation inhibitor fungicides, including multi-drug resistance strains. This study reports new insights into the use of bio-inspired RLs to control Z. tritici.


Assuntos
Ascomicetos/efeitos dos fármacos , Glicolipídeos/química , Glicolipídeos/farmacologia , Praguicidas/farmacologia , Doenças das Plantas/prevenção & controle , Folhas de Planta/efeitos dos fármacos , Triticum/efeitos dos fármacos , Ascomicetos/patogenicidade , Doenças das Plantas/microbiologia , Folhas de Planta/microbiologia , Triticum/microbiologia
18.
J Agric Food Chem ; 68(52): 15478-15489, 2020 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-33319980

RESUMO

Rhamnolipid is the main group of biosurfactants predominantly produced by Pseudomonas aeruginosa, a ubiquitous and opportunistic pathogen, which limits its large-scale exploitation. Thus, cost-effective rhamnolipid production from a newly isolated nonpathogenic Enterobacter sp. UJS-RC was investigated. The highest rhamnolipid production (4.4 ± 0.2 g/L) was achieved in a medium constituting agroindustrial wastes (sugarcane molasses and corn steep liquor) as substrates. Rhamnolipid exhibited reduced surface tension to 72-28 mN/m with an emulsification index of 75%. The structural analyses demonstrated the presence of methoxyl, carboxyl, and hydroxyl groups in rhamnolipid. Mass spectra indicated eight rhamnolipid congeners, where dirhamnolipid (m/z 650.01) was the dominant congener. Rhamnolipid inhibited biofilm formation of Staphylococcus aureus in a dose-dependent manner, supported by scanning electron microscopy disclosing the disruption of the microcolony/exopolysaccharide matrix. Rhamnolipid's ability to generate reactive oxygen species has thrown light on the mechanism through which the killing of test bacteria may occur.


Assuntos
Biofilmes/efeitos dos fármacos , Enterobacter/metabolismo , Glicolipídeos/metabolismo , Glicolipídeos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Tensoativos/metabolismo , Agricultura , Biotransformação , Enterobacter/química , Glicolipídeos/química , Melaço/análise , Saccharum/metabolismo , Saccharum/microbiologia , Staphylococcus aureus/fisiologia , Tensoativos/química , Resíduos/análise , Microbiologia da Água , Zea mays/metabolismo , Zea mays/microbiologia
19.
Int J Syst Evol Microbiol ; 70(10): 5576-5585, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32941125

RESUMO

Two novel Gram-stain-positive bacteria, designated as SCSIO 52909T and SCSIO 52915T, were isolated from a deep-sea sediment sample collected at about 3448 m water depth of the South China Sea. Phenotypic, chemotaxonomic and genomic characteristics were investigated. These strains were aerobic and tested positive for catalase activity, oxidase activity and nitrate reduction. Optimal growth occurred at 28 °C, pH 7 and 3% salinity over 14 days cultivation. Its peptidoglycan structure was type A3α (l-Lys-l-Ala) and the only menaquinone was MK-8. Both strains possessed diphosphatidylglycerol, phosphatidylglycerol, an unidentified phosphoglycolipid, an unidentified glycolipid and an unidentified phospholipid. Their major fatty acids differed, but both contained iso-branched components of C16 : 0 12-methyl. Genome sequencing revealed two large genomes of 4.58 Mbp with G+C content of 67.0 mol% in SCSIO 52909T and of 4.42 Mbp with G+C content of 69.1 % in SCSIO 52915T. The two novel strains encoded genes for metabolism that are absent in most other Rubrobacter species, and possessed many more gene copy numbers of alkaline phosphatase and thioredoxin reductase. Results of gANI and 16S rRNA gene analyses suggested that the two strains represent two new species, with 74.9, 95.0 % pairwise similarity between each other, and less than 74.3 and 93.5 % to other recognized Rubrobacter species, respectively. In the phylogenetic analysis, strains SCSIO 52909T and SCSIO 52915T were separately clustered together and formed a well-separated phylogenetic branch distinct from the other known species in the genus Rubrobacter. Based on the data presented here, these two strains should be recognized as two new species in the genus Rubrobacter, for which the names Rubrobacter tropicus sp. nov., with the type strain SCSIO 52909T (=KCTC 49412T=CGMCC 1.13853T), and Rubrobacter marinus sp. nov., with the type strain SCSIO 52915T (=KCTC 49411T=CGMCC 1.13852T), are proposed.


Assuntos
Actinobacteria/classificação , Sedimentos Geológicos/microbiologia , Filogenia , Água do Mar/microbiologia , Actinobacteria/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Oceano Pacífico , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
20.
Int J Syst Evol Microbiol ; 70(10): 5445-5452, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32886595

RESUMO

A Gram-stain-positive, aerobic, catalase-positive, oxidase-negative, non-mycelium-forming, motile, rod-shaped with one polar flagellum actinobacterium, designated E918T, was isolated from a desert soil collected in Cholistan desert, Pakistan. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain E918T belonged to the genus Arthrobacter and was most closely related to Arthrobacter deserti CGMCC 1.15091T (97.2 % similarity). The peptidoglycan was of the A3α type and the whole-cell sugar profile was found to contain galactose. The major menaquinone was MK-9(H2). The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and two unidentified glycolipids. The major fatty acids identified were anteiso-C15 : 0 and anteiso-C17 : 0. The G+C content of the genomic DNA was 68.69 mol%. The digital DNA-DNA hybridization and average nucleotide identity values between strain E918T and A. deserti CGMCC 1.15091T were 28.0 and 83.4%, respectively. On the basis of its phylogenetic, phenotypic and chemotaxonomic features, strain E918T was considered to represent a novel species of the genus Arthrobacter, for which the name Arthrobacter mobilis sp. nov. is proposed. The type strain of Arthrobacter mobilis is E918T (=JCM 33392T=CGMCC 1.16978T).


Assuntos
Arthrobacter/classificação , Clima Desértico , Filogenia , Microbiologia do Solo , Arthrobacter/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Hibridização de Ácido Nucleico , Paquistão , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
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