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Glycoconjugate Journal Apr 2021Pandoraea sp. is an emerging Gram-negative pathogen in cystic fibrosis causing severe and persistent inflammation and damage of the lungs. The molecular mechanisms...
Pandoraea sp. is an emerging Gram-negative pathogen in cystic fibrosis causing severe and persistent inflammation and damage of the lungs. The molecular mechanisms underlying the high pathogenicity of Pandoraea species are still largely unknown. As Gram-negatives, Pandoraea sp. express lipopolysaccharides (LPS) whose recognition by the host immune system triggers an inflammatory response aimed at the bacterial eradication from the infected tissues. The degree of the inflammatory response strongly relies on the fine structure of the LPS and, in particular, of its glycolipid moiety, i.e. the lipid A. Here we report the structure of the lipid A isolated from the LPS of a chronic strain of P. pulmonicola (RL 8228), one of the most virulent identified so far among the Pandoraea species. Our data demonstrated that the examined chronic strain produces a smooth-type LPS with a complex mixture of hypoacylated lipid A species displaying, among other uncommon characteristics, the 2-hydroxylation of some of the acyl chains and the substitution by an additional glucosamine on one or both the phosphate groups.
Topics: Acylation; Burkholderiaceae; Cystic Fibrosis; Humans; Lipid A; Lipopolysaccharides; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
PubMed: 33048281
DOI: 10.1007/s10719-020-09954-8 -
Journal of the Association of Medical... Oct 2020Diagnosis and clinical management of pulmonary infections in lung transplant patients are challenging. The increased diversity of bacterial species identified from...
Diagnosis and clinical management of pulmonary infections in lung transplant patients are challenging. The increased diversity of bacterial species identified from clinical samples with novel proteomics-based systems can further complicate clinical decision making in this highly vulnerable population. Whether newly recognized organisms are colonizers or true pathogens often remains controversial since symptoms causality and impact on lung function is often unknown. We present the case of a 48-year-old female lung transplant patient with sp infection. We review and discuss the role of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) for accurate bacterial identification. We report on therapeutic management and clinical outcome.
PubMed: 36341313
DOI: 10.3138/jammi-2020-0001 -
Ecotoxicology and Environmental Safety Dec 2020Understanding the degradation of pentachlorophenol (PCP) by indigenous microorganisms stimulated by an electron donor and shuttle in paddy soil, and the influences of...
Understanding the degradation of pentachlorophenol (PCP) by indigenous microorganisms stimulated by an electron donor and shuttle in paddy soil, and the influences of PCP/electron donor/shuttle on the native microbial community are important for biodegradation and ecological and environmental safety. Previous studies focused on the kinetics and the microbial actions of PCP degradation, however, the effects of toxic and antimicrobial PCP and electron donor/shuttle on the microbial community diversity and composition in paddy soil are poorly understood. In this study, the effects of PCP, an electron donor (lactate), and the electron shuttle (anthraquinone-2, 6-disulfonate, AQDS) on the microbial community in paddy soil were investigated. The results showed that the presence of PCP reduced the microbial diversity compared to the control during PCP degradation, while increased the microbial diversity was observed in response to lactate and AQDS. The addition of PCP stimulated the microorganisms involved in PCP dechlorination, including Clostridium, Desulfitobacterium, Pandoraea, and unclassified Veillonellaceae, which were dormant in raw soil without PCP stress. In all of the treatments with PCP, the addition of lactate or AQDS enhanced PCP dechlorination by stimulating the growth of functional groups involved in PCP dechlorination and by changing the microbial community during dechlorination process. The microbial community tended to be uniform after complete PCP degradation (28 days). However, when lactate and AQDS were present simultaneously in PCP-contaminated soil, lactate acted as a carbon source or electron donor to promote the activities of microbial community, and AQDS changed the redox potential because of the production of reduced AQDS. These findings enhance our understanding of the effect of PCP and a biostimulation method for PCP biodegradation in soil ecosystems at the microbial community level, and suggest the appropriate selection of an electron donor/shuttle for accelerating the bioremediation of PCP-contaminated soils.
Topics: Anthraquinones; Biodegradation, Environmental; Electron Transport; Lactic Acid; Microbiota; Pentachlorophenol; Soil; Soil Microbiology; Soil Pollutants
PubMed: 32950805
DOI: 10.1016/j.ecoenv.2020.111328 -
Animal Bioscience Jan 2021Temperature could influence protein and amino acid deposition as well as gut microbiota profile and composition. However, the specific effects of ambient temperature on...
OBJECTIVE
Temperature could influence protein and amino acid deposition as well as gut microbiota profile and composition. However, the specific effects of ambient temperature on amino acids deposition and gut microbiota composition remain insufficiently understood.
METHODS
A total of 300 one-day-old Avian broilers were randomly divided into three groups and reared at high, medium, and low temperature (HT, MT, and LT), respectively. Breast muscle and fecal samples were collected for amino acid composition analysis and 16S rRNA gene sequence analysis.
RESULTS
Our data showed that compared to the MT group, there was a decrease of muscle leucine and tyrosine (p<0.05), as well as an increase of methionine in the HT group (p<0.05) and a decrease of serine in the LT group. Examination of microbiota shift revealed that at genus level, the relative abundance of Turicibacter and Parabacteroides was increased in the HT group (p<0.05) and that the relative abundances of Pandoraea, Achromobacter, Prevotella, Brevundimonas, and Stenotrophomonas in the LT group were higher than those in the MT group (p<0.05). In addition, there were substantial correlations between microbes and amino acids. In the HT group. Turicibacter was negatively correlated with aspartic acid and tyrosine, whereas Parabacteroides was positively correlated with methionine (p<0.05). In the LT group, there were multiple positive correlations between Achromobacter and arginine, isoleucine or tyrosine; between Prevotella and cysteine or phenylalanine; between Brevundimonas and cysteine; and between Stenotrophomonas and cysteine as well as a negative correlation between Stenotrophomonas and serine.
CONCLUSION
Our findings demonstrated that amino acid content of breast muscle and intestinal microbiota profile was affected by different ambient temperatures. Under heat exposure, augmented abundance of Parabacteroides was correlated with elevated methionine. Low temperature treatment may affect muscle tyrosine content through the regulation of Achromobacter.
PubMed: 32898964
DOI: 10.5713/ajas.20.0314 -
Journal of Environmental Management Oct 2020Aerobic granular sludge (AGS) is a type of biofilm with good sedimentation and density, high biomass, high organic load tolerance and toxicity resistance....
Aerobic granular sludge (AGS) is a type of biofilm with good sedimentation and density, high biomass, high organic load tolerance and toxicity resistance. Oxytetracycline (OTC) is an antibiotic widely used in livestock and aquaculture, and its low absorption and high residue bring many risks and harms to the ecological environment. In this study, an OTC-degrading strain TJ3 was isolated from AGS and identified as Pandoraea sp. The biodegradation characteristics of OTC by strain TJ3 under different environmental conditions were also investigated. The results showed that the optimal initial pH value and temperature for the culture strain were 6.0 and 30 °C, respectively. At an inoculation dose of 6% (v/v), the removal rate of OTC by strain TJ3 was remarkable (59.4%). Furthermore, when the sodium acetate was present as an additional substrate, the biomass and the OTC removal rate of strain TJ3 were improved. The biodegradability of strain TJ3 to OTC was proved by LC-QTOF/MS, and two possible biotransformation products, i.e. m/z 416 and 219, were identified. In the bioaugmentation experiments of AGS by strain TJ3, the average OTC removal rate was 92.89% after the stable operation of bioreactor. The chemical oxygen demand (COD), ammonium nitrogen (NH-N) and total phosphorus (TP) were efficiently removed. The microbial community structure had significantly changed at the genus level, and the relative abundance of Zoogloea, Pandoraea, Cloacibacterium and Desulfovibrio increased evidently. These results implied that the OTC removal performance and the structural stability of AGS were improved. In this study, Pandoraea sp. TJ3 was applied to removal OTC for the first time, and results showed that Pandoraea sp. TJ3 may be a new auxiliary bacterial resource for the biodegradation of OTC and a potential candidate in the treatment of antibiotic wastewater.
Topics: Aerobiosis; Bacteria; Biological Oxygen Demand Analysis; Bioreactors; Nitrogen; Oxytetracycline; Sewage; Waste Disposal, Fluid
PubMed: 32738758
DOI: 10.1016/j.jenvman.2020.111115 -
Bioprocess and Biosystems Engineering Nov 2020In this study, the roles of extracellular polymeric substances (EPSs) excreted by Pandoraea sp. XY-2 in the removal of tetracycline (TC) were investigated. In the early...
In this study, the roles of extracellular polymeric substances (EPSs) excreted by Pandoraea sp. XY-2 in the removal of tetracycline (TC) were investigated. In the early stage, TC in the solution was mainly removed by the adsorption of EPSs, which accounted for 20% of TC. Thereafter, large amount of TC was transported into the intracellular and biodegraded. EPSs was extracted and the contents of polyprotein and polysaccharides reached their maximum values (30.84 mg/g and 11.15 mg/g) in the first four days. Fourier transform infrared spectroscopy analysis revealed that hydroxyl, methylidyne, methylene and amide I groups in EPSs participated in the adsorption of TC. Furthermore, three-dimensional excitation-emission matrix fluorescence spectroscopy analysis revealed that TC caused the quenching of EPSs fluorescent groups. The quenching mechanism was attributed to static quenching and protein-like substances in EPSs from Pandoraea sp. XY-2 dominated the TC adsorption process. Bioinformatic analysis of Pandoraea sp. XY-2 genome identified multiple genes involved in exopolysaccharide synthesis and EPSs formation. The insights gained in this study might provide a better understanding about the adsorption process of EPSs in tetracycline-contaminated environment.
Topics: Adsorption; Anti-Bacterial Agents; Biotechnology; Burkholderiaceae; Extracellular Polymeric Substance Matrix; Methane; Polymers; Polyproteins; Polysaccharides; Sewage; Spectrometry, Fluorescence; Spectroscopy, Fourier Transform Infrared; Tetracycline; Time Factors; Water Pollutants, Chemical; Water Purification
PubMed: 32500436
DOI: 10.1007/s00449-020-02384-8 -
Ecotoxicology and Environmental Safety Jun 2020Phthalate esters (PAEs), a class of toxic anthropogenic compounds, have been predominantly used as additives or plasticizers, and great concern and interests have been...
Phthalate esters (PAEs), a class of toxic anthropogenic compounds, have been predominantly used as additives or plasticizers, and great concern and interests have been raised regarding its environmental behavior and degradation mechanism. In the present study, a bacterial consortium consisting of Microbacterium sp. PAE-1 and Pandoraea sp. PAE-2 was isolated by the enrichment method, which could degrade dibutyl phthalate (DBP) completely by biochemical cooperation. DBP was converted to phthalic acid (PA) via monobutyl phthalate (MBP) by two sequential hydrolysis steps in strain PAE-1, and then PA was further degraded by strain PAE-2. Strain PAE-1 could hydrolyze many dialkyl Phthalate esters (PAEs) including dimethyl, diethyl, dibutyl, dipentyl, benzyl butyl, dihexyl, di-(2-ethyhexyl) and their corresponding monoalkyl PAEs. Two esterase genes named dpeH and mpeH, located in the same transcription unit, were cloned from strain PAE-1 by the shotgun method and heterologously expressed in Escherichia. coli (DE3). The Km and kcat values of DpeH for DBP were 9.60 ± 0.97 μM and (2.72 ± 0.06) × 10 s, while those of MpeH for MBP were 18.61 ± 2.00 μM and (5.83 ± 1.00) × 10 s, respectively. DpeH could only hydrolyze dialkyl PAEs to the corresponding monoalkyl PAEs, which were then hydrolyzed to PA by MpeH. DpeH shares the highest similarity (53%) with an alpha/beta hydrolase from Microbacterium sp. MED-G48 and MpeH shows only 25% identity with a secreted lipase from Trichophyton benhamiae CBS 112371, indicating that DpeH and MpeH are two novel hydrolases against PAEs.
Topics: Actinobacteria; Burkholderiaceae; Dibutyl Phthalate; Environmental Pollutants; Esterases; Genes, Bacterial; Hydrolysis; Lipase; Microbial Consortia; Phthalic Acids; Plasticizers
PubMed: 32220793
DOI: 10.1016/j.ecoenv.2020.110517 -
Microbiology Resource Announcements Mar 2020is a newly identified Gram-negative bacterial species that was isolated from the respiratory tract of an Australian cystic fibrosis patient. The complete assembled...
is a newly identified Gram-negative bacterial species that was isolated from the respiratory tract of an Australian cystic fibrosis patient. The complete assembled genome sequences of two consecutive isolates (second isolate collected 11 months after antibiotic treatment) from the same individual are presented here.
PubMed: 32217674
DOI: 10.1128/MRA.00060-20 -
Antimicrobial Agents and Chemotherapy Mar 2020
Topics: Cystic Fibrosis; Glucose; Gram-Negative Bacteria; Humans; Microbial Sensitivity Tests; beta-Lactamase Inhibitors
PubMed: 32209566
DOI: 10.1128/AAC.00011-20 -
The ISME Journal Jul 2020In addition to abiotic triggers, biotic factors such as microbial symbionts can alter development of multicellular organisms. Symbiont-mediated morphogenesis is...
In addition to abiotic triggers, biotic factors such as microbial symbionts can alter development of multicellular organisms. Symbiont-mediated morphogenesis is well-investigated in plants and marine invertebrates but rarely in insects despite the enormous diversity of insect-microbe symbioses. The bean bug Riptortus pedestris is associated with Burkholderia insecticola which are acquired from the environmental soil and housed in midgut crypts. To sort symbionts from soil microbiota, the bean bug develops a specific organ called the "constricted region" (CR), a narrow and symbiont-selective channel, located in the midgut immediately upstream of the crypt-bearing region. In this study, inoculation of fluorescent protein-labeled symbionts followed by spatiotemporal microscopic observations revealed that after the initial passage of symbionts through the CR, it closes within 12-18 h, blocking any potential subsequent infection events. The "midgut closure" developmental response was irreversible, even after symbiont removal from the crypts by antibiotics. It never occurred in aposymbiotic insects, nor in insects infected with nonsymbiotic bacteria or B. insecticola mutants unable to cross the CR. However, species of the genus Burkholderia and its outgroup Pandoraea that can pass the CR and partially colonize the midgut crypts induce the morphological alteration, suggesting that the molecular trigger signaling the midgut closure is conserved in this bacterial lineage. We propose that this drastic and quick alteration of the midgut morphology in response to symbiont infection is a mechanism for stabilizing the insect-microbe gut symbiosis and contributes to host-symbiont specificity in a symbiosis without vertical transmission.
Topics: Animals; Bacterial Infections; Burkholderia; Digestive System; Heteroptera; Symbiosis
PubMed: 32203122
DOI: 10.1038/s41396-020-0633-3