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Genome Announcements Jun 2015We report the draft genome of Brevundimonas diminuta strain XGC1, isolated from a tuberculosis-infected patient in Gujarat, India. This study also reveals that the...
We report the draft genome of Brevundimonas diminuta strain XGC1, isolated from a tuberculosis-infected patient in Gujarat, India. This study also reveals that the B. diminuta XGC1 strain has acquired mutation to confer resistance to quinolone drugs.
PubMed: 26112790
DOI: 10.1128/genomeA.00686-15 -
Molecules (Basel, Switzerland) Mar 2020Enzyme-catalyzed hydrolysis of echothiophate, a P-S bonded organophosphorus (OP) model, was spectrofluorimetrically monitored, using Calbiochem Probe IV as the thiol...
Enzyme-catalyzed hydrolysis of echothiophate, a P-S bonded organophosphorus (OP) model, was spectrofluorimetrically monitored, using Calbiochem Probe IV as the thiol reagent. OP hydrolases were: the G117H mutant of human butyrylcholinesterase capable of hydrolyzing OPs, and a multiple mutant of phosphotriesterase, GG1, designed to hydrolyze a large spectrum of OPs at high rate, including V agents. Molecular modeling of interaction between Probe IV and OP hydrolases (G117H butyrylcholinesterase, GG1, wild types of and phosphotriesterases, and human paraoxonase-1) was performed. The high sensitivity of the method allowed steady-state kinetic analysis of echothiophate hydrolysis by highly purified G117H butyrylcholinesterase concentration as low as 0.85 nM. Hydrolysis was michaelian with = 0.20 ± 0.03 mM and = 5.4 ± 1.6 min. The GG1 phosphotriesterase hydrolyzed echothiophate with a high efficiency ( = 2.6 ± 0.2 mM; = 53400 min). With a = (2.6 ± 1.6) × 10 Mmin, GG1 fulfills the required condition of potential catalytic bioscavengers. quantum mechanics/molecular mechanics (QM/MM) and molecular docking indicate that Probe IV does not interact significantly with the selected phosphotriesterases. Moreover, results on G117H mutant show that Probe IV does not inhibit butyrylcholinesterase. Therefore, Probe IV can be recommended for monitoring hydrolysis of P-S bonded OPs by thiol-free OP hydrolases.
Topics: Biocatalysis; Butyrylcholinesterase; Caulobacteraceae; Echothiophate Iodide; Enzymes; Humans; Hydrolysis; Kinetics; Molecular Docking Simulation; Mutant Proteins; Organophosphorus Compounds; Phosphoric Triester Hydrolases; Spectrometry, Fluorescence; Sulfolobus
PubMed: 32192230
DOI: 10.3390/molecules25061371 -
3 Biotech Dec 2016Endophytes are microorganisms which live symbiotically with almost all varieties of plant and in turn helping the plant in a number of ways. Instead of satisfactory...
Endophytes are microorganisms which live symbiotically with almost all varieties of plant and in turn helping the plant in a number of ways. Instead of satisfactory surface sterilization approaches, repeatedly occurring bacterial growth on in vitro rootstock cultures of peach and pear was identified and isolated as endophytic bacteria in our present study. Five different isolates from peach rootstocks were molecularly identified by 16S rRNA gene sequencing as Brevundimonas diminuta, Leifsonia shinshuensis, Sphingomonas parapaucimobilis Brevundimonas vesicularis, Agrobacterium tumefaciens while two endophytic isolates of pear were identified as Pseudoxanthomonas mexicana, and Stenotrophomonas rhizophilia. Identified endophytes were also screened for their potential of plant growth promotion according to indoleacetic acid (IAA) production, nitrogen fixation, solubilization of phosphate and production of siderophore. All seven endophytic isolates have shown positive results for IAA, nitrogen fixation and phosphate solubilization tests. However, two out of seven isolates showed positive results for siderophore production. On the basis of these growth promoting competences, isolated endophytes can be presumed to have significant influence on the growth of host plants. Future studies required to determine the antimicrobial susceptibility profile and potential application of these isolates in biological control, microbial biofertilizers and degradative enzyme production.
PubMed: 28330195
DOI: 10.1007/s13205-016-0442-6 -
European Journal of Hospital Pharmacy :... Dec 2023To investigate the container closure integrity of a closed system transfer device syringe adaptor lock in combination with disposable Luer-Lock syringes as the terminal...
OBJECTIVES
To investigate the container closure integrity of a closed system transfer device syringe adaptor lock in combination with disposable Luer-Lock syringes as the terminal closure device. The UK National Health Service (NHS) Pharmaceutical Quality Assurance Committee (PQAC) requires syringe integrity data for final storage devices of aseptic products such as chemotherapy drugs when prepared in advance and stored before use, as is standard practice for dose banded drugs. The assessment comprised both physical and microbial integrity testing of the combination closed system/Luer-Lock syringe containers at syringe sizes of 1 mL, 20 mL, and 50 mL.
METHODS
Integrity testing was performed as described in the NHS Pharmaceutical Quality Assurance Committee yellow cover document, second edition 2013 'Protocols for the Integrity Testing of Syringes', with Chemfort (Simplivia, IL) syringe adaptor lock (SAL) devices as replacement for sterile blind hubs. Microbiological integrity was assessed according to method 1 part 1.4 using at 32°C for up to 14 days of contact time. Two positive control devices per syringe size were tested using a blind hub cap as closure which was loosened before the test. Physical integrity was assessed using method 3 of the yellow cover document which is a dye intrusion method. Dye intrusion was assessed both visually and using a validated ultraviolet-visible spectrophotometer method. For each size/batch of test articles a positive control device (n=1) was assessed using a wire wrapped around the syringe plunger tip deliberately compromising integrity. Negative controls for each size (n=1) consisted of devices not immersed in methylene blue dye.
RESULTS
Chemfort syringe adaptor lock/Luer-Lock syringe combinations were shown to be: (1) free of microbiological contamination after 14 days of contact time (n=60); and (2) free of dye intrusion at all syringe sizes tested (n=61 in total). The data demonstrate 100% closure integrity of the final container system when the Chemfort syringe adaptor lock replaces the syringe hub as the terminal closure device. All positive control devices demonstrated system suitability as container integrity was compromised in all positive control tests. All negative controls were negative for microbial and dye intrusion.
CONCLUSIONS
Syringe adaptor lock components complied with the NHS Pharmaceutical Quality Assurance Committee yellow cover document syringe integrity requirements when used as the terminal closure of Luer-Lock disposable syringes from 1 mL up to 50 mL. Therefore, syringe adaptor lock (Chemfort) can be used as the terminal closure system for pre-filled syringes of chemotherapeutic drug products prepared in advance in UK NHS pharmacy technical services.
Topics: Drug Contamination; Drug Packaging; Pharmaceutical Preparations; State Medicine; Syringes
PubMed: 35410874
DOI: 10.1136/ejhpharm-2021-003148 -
Medicina (Kaunas, Lithuania) Nov 2021is rarely described in clinical specimens, never at the umbilical stump. Most of the reported cases are in patients with underlying pathologies. We must integrate this...
is rarely described in clinical specimens, never at the umbilical stump. Most of the reported cases are in patients with underlying pathologies. We must integrate this microorganism in the etiological agents of nosocomial infections, but much remains to be understood about its virulence. We present a case of umbilical stump infection (omphalitis) caused by , in a preterm and hypotrophic new-born and discuss the diagnosis of this bacterium and its role as responsible of nosocomial neonatal infections.
Topics: Caulobacteraceae; Cross Infection; Democratic Republic of the Congo; Humans; Infant, Low Birth Weight; Infant, Newborn
PubMed: 34833445
DOI: 10.3390/medicina57111227 -
Biochemistry Aug 2020The COVID-19 pandemic threatens to overwhelm healthcare systems around the world. The only current FDA-approved treatment, which directly targets the virus, is the...
The COVID-19 pandemic threatens to overwhelm healthcare systems around the world. The only current FDA-approved treatment, which directly targets the virus, is the ProTide prodrug remdesivir. In its activated form, remdesivir prevents viral replication by inhibiting the essential RNA-dependent RNA polymerase. Like other ProTide prodrugs, remdesivir contains a chiral phosphorus center. The initial selection of the ()-diastereomer for remdesivir was reportedly due to the difficulty in producing the pure ()-diastereomer of the required precursor. However, the two currently known enzymes responsible for the initial activation step of remdesivir are each stereoselective and show differential tissue distribution. Given the ability of the COVID-19 virus to infect a wide array of tissue types, inclusion of the ()-diastereomer may be of clinical significance. To help overcome the challenge of obtaining the pure ()-diastereomer of remdesivir, we have developed a novel chemoenzymatic strategy that utilizes a stereoselective variant of the phosphotriesterase from to enable the facile isolation of the pure ()-diastereomer of the chiral precursor for the chemical synthesis of the ()-diastereomer of remdesivir.
Topics: Adenosine Monophosphate; Alanine; Antiviral Agents; Betacoronavirus; COVID-19; Caulobacteraceae; Coronavirus Infections; Humans; Molecular Structure; Pandemics; Phosphoric Triester Hydrolases; Pneumonia, Viral; RNA-Dependent RNA Polymerase; SARS-CoV-2; Virus Replication
PubMed: 32786401
DOI: 10.1021/acs.biochem.0c00591 -
Biotechnology and Bioengineering Mar 2020The widely used 0.2/0.22 µm polymer sterile filters were developed for small molecule and protein sterile filtration but are not well-suited for the production of...
The widely used 0.2/0.22 µm polymer sterile filters were developed for small molecule and protein sterile filtration but are not well-suited for the production of large nonprotein biological therapeutics, resulting in significant yield loss and production cost increases. Here, we report on the development of membranes with isoporous sub-0.2 μm rectangular prism pores using silicon micromachining to produce microslit silicon nitride (MSN) membranes. The very high porosity (~33%) and ultrathin (200 nm) nature of the 0.2 µm MSN membranes results in a dramatically different structure than the traditional 0.2/0.22 µm polymer sterile filter, which yielded comparable performance properties (including gas and hydraulic permeance, maximum differential pressure tolerance, nanoparticle sieving/fouling behavior). The results from bacteria retention tests, conducted according to the guidance of regulatory agencies, demonstrated that the 0.2 µm MSN membranes can be effectively used as sterile filters. It is anticipated that the results and technologies presented in this study will find future utility in the production of non-protein biological therapeutics and in other biological and biomedical applications.
Topics: Biological Products; Caulobacteraceae; Drug Contamination; Equipment Design; Filtration; Membranes, Artificial; Nanostructures; Porosity; Silicon Compounds
PubMed: 31784974
DOI: 10.1002/bit.27240 -
American Journal of Health-system... Aug 2015Specific deviations from United States Pharmacopeia standards were analyzed to investigate the factors allowing an outbreak of Serratia marcescens bloodstream infections...
PURPOSE
Specific deviations from United States Pharmacopeia standards were analyzed to investigate the factors allowing an outbreak of Serratia marcescens bloodstream infections in patients receiving compounded amino acid solutions.
METHODS
Filter challenge experiments using the outbreak strain of S. marcescens were compared with those that used the filter challenge organism recommended by ASTM International (Brevundimonas diminuta ATCC 19162) to determine the frequency and degree of organism breakthrough. Disk and capsule filters (0.22- and 0.2-μm nominal pore size, respectively) were challenged with either the outbreak strain of S. marcescens or B. diminuta ATCC 19162. The following variables were compared: culture conditions in which organisms were grown overnight or cultured in sterile water (starved), solution type (15% amino acid solution or sterile water), and filtration with or without a 0.5-μm prefilter.
RESULTS
Small-scale, syringe-driven, disk-filtration experiments of starved bacterial cultures indicated that approximately 1 in every 1,000 starved S. marcescens cells (0.12%) was able to pass through a 0.22-μm nominal pore-size filter, and about 1 in every 1,000,000 cells was able to pass through a 0.1-μm nominal pore-size filter. No passage of the B. diminuta ATCC 19162 cells was observed with either filter. In full-scale experiments, breakthrough was observed only when 0.2-μm capsule filters were challenged with starved S. marcescens in 15% amino acid solution without a 0.5-μm prefiltration step.
CONCLUSION
Laboratory simulation testing revealed that under certain conditions, bacteria can pass through 0.22- and 0.2-μm filters intended for sterilization of an amino acid solution. Bacteria did not pass through 0.2-μm filters when a 0.5-μm prefilter was used.
Topics: Bacteremia; Disease Outbreaks; Drug Compounding; Filtration; Humans; Parenteral Nutrition; Pharmacy Service, Hospital; Serratia Infections; Serratia marcescens; United States
PubMed: 26195654
DOI: 10.2146/ajhp150141 -
PeerJ 2019Increasing evidence has confirmed the importance of plant-associated bacteria for plant growth and productivity, and thus it is hypothesized that interactions between...
Increasing evidence has confirmed the importance of plant-associated bacteria for plant growth and productivity, and thus it is hypothesized that interactions between bacteria and alien plants might play an important role in plant invasions. However, the diversity of the bacterial communities associated with invasive plants is poorly understood. We therefore investigated the diversity of rhizospheric and endophytic bacteria associated with the invasive annual plant L. (Asteraceae) based on 16S rRNA gene data obtained from 57 samples of four populations in a subtropical mountainous area in central China. Significant differences in diversity were observed between plant compartments. Specifically, the rhizosphere harbored many more bacterial operational taxonomic units and showed higher alpha diversity than the leaf and root endospheres. The relative abundance profiles of the bacterial community composition differed substantially between the compartments and populations, especially at the phylum and family levels. However, the top five phyla (Proteobacteria, Firmicutes, Bacteroidetes, Actinobacteria, and Acidobacteria) accounted for more than 90% of all the bacterial communities. Moreover, similar endophytic communities with a shared core set of bacteria were observed from different populations. Heavy-metal-resistant, phosphate-solubilizing bacteria (), nitrogen-fixing bacteria (), and cold-resistant bacteria () were present in the endosphere at relatively high abundance. This study, which reveals the structure of bacterial communities and their putative function in invasive plants, is the first step in investigating the role of plant-bacteria interactions in the invasion of this species in China.
PubMed: 30643678
DOI: 10.7717/peerj.6162 -
International Journal of Environmental... Jun 2016Animal manure is commonly used as fertilizer for agricultural crops worldwide, even though it is believed to contribute to the spread of antibiotic resistance from...
Animal manure is commonly used as fertilizer for agricultural crops worldwide, even though it is believed to contribute to the spread of antibiotic resistance from animal intestines to the soil environment. However, it is unclear whether and how there is any impact of manure fertilization on populations and community structure of antibiotic-resistant endophytic bacteria (AREB) in plant tissues. To investigate the effect of manure and organic fertilizer on endophytic bacterial communities, pot experiments were performed with pakchoi grown with the following treatments: (1) non-treated; (2) chicken manure-treated and (3) organic fertilizer-treated. Manure or organic fertilizer significantly increased the abundances of total cultivable endophytic bacteria (TCEB) and AREB in pakchoi, and the effect of chicken manure was greater than that of organic fertilizer. Further, 16S rDNA sequencing and the phylogenetic analysis indicated that chicken manure or organic fertilizer application increased the populations of multiple antibiotic-resistant bacteria (MARB) in soil and multiple antibiotic-resistant endophytic bacteria (MAREB) in pakchoi. The identical multiple antibiotic-resistant bacterial populations detected in chicken manure, manure- or organic fertilizer-amended soil and the vegetable endophytic system were Brevundimonas diminuta, Brachybacterium sp. and Bordetella sp., suggesting that MARB from manure could enter and colonize the vegetable tissues through manure fertilization. The fact that some human pathogens with multiple antibiotic resistance were detected in harvested vegetables after growing in manure-amended soil demonstrated a potential threat to human health.
Topics: Animals; Anti-Bacterial Agents; Bacteria; Chickens; Crops, Agricultural; DNA, Ribosomal; Drug Resistance, Multiple, Bacterial; Fertilizers; Humans; Manure; Phylogeny; Soil Microbiology; Vegetables
PubMed: 27376311
DOI: 10.3390/ijerph13070662