The genome of the soil bacterium Pseudomonas putida KT2440 bears two virtually identical arsRBCH operons putatively encoding resistance to inorganic arsenic species. Single and double chromosomal deletions in each of these ars clusters of this bacterium were tested for arsenic sensitivity and found that the contribution of each operon to the resistance to the metalloid was not additive, as either cluster sufficed to endow cells with high-level resistance. However, otherwise identical traits linked to each of the ars sites diverged when temperature was decreased. Growth of the various mutants at 15°C (instead of the standard 30°C for P. putida) uncovered that ars2 affords a much higher resistance to As (III) than the ars1 counterpart. Reverse transcription polymerase chain reaction of arsB1 and arsB2 genes as well as lacZ fusions to the Pars1 and Pars2 promoters traced the difference to variations in transcription of the corresponding gene sets at each temperature. Functional redundancy may ...
Background|br /|The genetic network of the TOL plasmid pWW0 of the soil bacterium Pseudomonas putida mt-2 for catabolism of m-xylene is an archetypal model for environmental biodegradation of aromatic pollutants. Although nearly every metabolic and transcriptional component of this regulatory system is known to an extraordinary molecular detail, the complexity of its architecture is still perplexing. To gain an insight into the inner layout of this network a logic model of the TOL system was implemented, simulated and experimentally validated. This analysis made sense of the specific regulatory topology out on the basis of an unprecedented network motif around which the entire genetic circuit for m-xylene catabolism gravitates.|br /|Results|br /|The most salient feature of the whole TOL regulatory network is the control exerted by two distinct but still intertwined regulators (XylR and XylS) on expression of two separated catabolic operons (upper and lower) for catabolism of m-xylene. Following model
Pseudomonas putida KT2440 is the only fully sequenced P. putida strain. Thus, for transcriptomics and proteomics studies with other P. putida strains, the P. putida KT2440 genomic database serves as standard reference. The utility of KT2440 whole-genome, high-density oligonucleotide microarrays for transcriptomics studies of other Pseudomonas strains was investigated. To this end, microarray hybridizations were performed with genomic DNAs of subcultures of P. putida KT2440 (DSM6125), the type strain (DSM291T), plasmid pWW0-containing KT2440-derivative strain mt-2 (DSM3931), the solvent-tolerant P. putida S12, and several other Pseudomonas strains. Depending on the strain tested, 22 to 99% of all genetic elements were identified in the genomic DNAs. The efficacy of these microarrays to study cellular function was determined for all strains included in the study. The vast majority of DSM6125 genes encoding proteins of primary metabolism and genes involved in the catabolism of aromatic compounds ...
Cytochrome P450cam (a camphor hydroxylase) isolated from soil bacterium Pseudomonas putida shows potent importance in environmental applications such as the degradation of chlorinated organic pollutants and insect control agents. Introducing such chemicals can be hazardous to the environment due to their lack of biodegradation. In this thesis, I have studied the role of several P450cam mutants in the oxidation of 3-chloroindole to isatin and the role of wild type P450cam in the dealkylation of 1,4-dibutoxybenzene, a potent feeding-deterrent against stored product pests. Mutant (E156G/V247F/V253G/F256S) was the most active in the conversion of 3-chloroindole by P450cam. We propose two mechanisms for the dechlorination of 3-chloroindole by P450cam. To investigate structure-activity patterns of 1,4-dialkoxybenzenes against beetles, the octanol-water partition coefficients of selected dialkoxybenzenes were investigated. Furthermore, P. putida strain ATCC17453 was able to metabolize ...
An enzyme found in a bacterium that consumes nicotine for nitrogen and carbon shows potentials as another smoking cessation alternative.
The synthesis and degradation of polyhydroxyalkanoates (PHAs), the storage polymer of many bacteria, is linked to the operation of central carbon metabolism. To rationalize the impact of PHA accumulation on central carbon metabolism of the prototype bacterium Pseudomonas putida, we have revisited PHA production in quantitative physiology experiments in the wild-type strain vs. a PHA negative mutant growing under low nitrogen conditions. When octanoic acid was used as PHA precursor and as carbon and energy source, we have detected higher intracellular flux via acetyl-CoA in the mutant strain than in the wild type, which correlates with the stimulation of the TCA cycle and glyoxylate shunt observed on the transcriptional level. The mutant defective in carbon and energy storage spills the additional resources, releasing CO2 instead of generating biomass. Hence, P. putida operates the metabolic network to optimally exploit available resources and channels excess carbon and energy to storage via PHA, ...
High Cell Density (HCD) cultivation of bacteria is essential for the majority of industrial processes to achieve high volumetric productivity (g L(-1) h(-1) ) of a bioproduct of interest. This study developed a fed batch bioprocess using glucose as sole carbon and energy source for the HCD of the well described biocatalyst Pseudomonas putida KT2440 without the supply of oxygen enriched air. Growth kinetics data from batch fermentations were used for building a bioprocess model and designing feeding strategies. An exponential followed by linearly increasing feeding strategy of glucose was found to be effective in maintaining biomass productivity while also delaying the onset of dissolved oxygen (supplied via compressed air) limitation. A final cell dry weight (CDW) of 102 g L(-1) was achieved in 33 h with a biomass productivity of 3.1 g L(-1) h(-1) which are the highest ever reported values for P. putida strains using glucose without the supply of pure oxygen or oxygen enriched air. The ...
de Eugenio, L.I., García, P., Luengo, J.M., Sanz, J., San Román, J., García, J.L., and Prieto, M.A. (2007) Biochemical evidence that phaZ gene encodes a specific intracellular medium chain length polyhydroxyalkanoate depolymerase in Pseudomonas putida KT2442: characterization of a paradigmatic enzyme. J Biol Chem 282: 4951-4962 ...
TY - JOUR. T1 - Salicylate degradation by a cold-adapted Pseudomonas sp. AU - Ahn, Eunsol. AU - Choi, Ki Young. AU - Kang, Beom Sik. AU - Zylstra, Gerben J.. AU - Kim, Dockyu. AU - Kim, Eungbin. PY - 2017/6/1. Y1 - 2017/6/1. N2 - Pseudomonas sp. strain MC1 was characterized as a cold-adapted, naphthalene-degrading bacterium that is able to grow in a broad temperature range of 5-30°C. MC1 harbors a catabolic plasmid, designated pYIC1, which is almost identical to the archetypal NAH7 plasmid from the mesophilic bacterium Pseudomonas putida G7. On pYIC1, the catabolic genes for naphthalene degradation are clustered in two operons: nahAa-Ab-Ac-Ad-B-F-C-Q-E-D encoding the conversion of naphthalene to salicylate, and nahG-T-H-I-N-L-O-M-K-J encoding the conversion of salicylate through meta-cleavage pathway to pyruvate and acetyl CoA. NahH, the bona fide extradiol dioxygenase in MC1 salicylate metabolism, is thermolabile and is a cold-adapted enzyme. The thermal profiles of the NahH enzyme activities ...
A number of genetic determinants required for bacterial colonization of solid surfaces and biofilm formation have been identified in different micro-organisms. There are fewer accounts of mutations that favour the transition to a sessile mode of life. Here we report the isolation of random transposon Pseudomonas putida KT2440 mutants showing increased biofilm formation, and the detailed characterization of one of them. This mutant exhibits a complex phenotype, including altered colony morphology, increased production of extracellular polymeric substances and enhanced swarming motility, along with the formation of denser and more complex biofilms than the parental strain. Sequence analysis revealed that the pleiotropic phenotype exhibited by the mutant resulted from the accumulation of two mutations: a transposon insertion, which disrupted a predicted outer membrane lipoprotein, and a point mutation in lapG, a gene involved in the turnover of the large adhesin LapA. The contribution of each ...
We have cloned, sequenced, and heterologously expressed a periplasmic cytochrome c from a lupanine-utilizing Pseudomonas putida strain. Aerobic batch cultivation of Escherichia coli TB1 harboring the cytochrome c gene placed downstream of the lac promoter in pUC9 vector resulted in significant production of the holo-cytochrome c in the periplasm (4 mg of hemoprotein/liter of culture). The recombinant cytochrome c was purified to homogeneity and was found to be functional in accepting electrons from lupanine hydroxylase while catalyzing hydroxylation of lupanine. Comparison of the N-terminal amino acid sequence of the isolated cytochrome c with that deduced from the DNA sequence indicated that the signal sequence was processed at the bond position predicted by the SigPep program. The molecular size of the cytochrome c determined by electrospray mass spectrometry (9,595) was in precise agreement with that predicted from the nucleotide sequence ...
Pseudomonas putida ATCC ® 47054D-5™ Designation: Genomic DNA from Pseudomonas putida strain KT2440 TypeStrain=False Application:
Coloured scanning electron micrograph (SEM) of Pseudomonas putida, Gram-negative, aerobic, enteric, rod prokaryote. Pseudomonas putida is a ubiquitous soil bacterium. Strains of P. putida have the ability to degrade organic solvents or hydrocarbons. This strain was isolated from a soil environment that had high levels of caffeine. It is known to biodegrade caffeine. Thus different strains of Pseudomonas putida can be used for bioremediation. Magnification: x1,600 when shortest axis printed at 25 millimetres. - Stock Image C032/1985
Large externalized, repeat-rich proteins are emerging as important factors in the attachment of bacteria to biotic and abiotic surfaces. An intriguing new study of the plant-associated terrestrial microbe Pseudomonas putida by Manuel Espinosa-Urgels group that is reported in this issue of Molecular Microbiology has revealed that LapF, a huge protein (, 6000 aa) associated with the cell surface, is required for microcolony assembly from single attached cells, and in turn, formation of biofilms. Mutants defective in IapF exhibit competitive deficiencies in the rhizosphere. On both biotic and abiotic surfaces, these mutants undergo normal irreversible attachment, but cannot advance beyond this point to form multicellular clusters. The lapF phenotype is nutritionally conditional and is only manifested under a subset of growth regimes. Accordingly, lapF gene expression is controlled by the stress-responsive sigma factor RpoS and is elevated within growing microcolonies on abiotic surfaces and plant ...
HERNANDEZ-MONTIEL, Luis G et al. Efficiency of two inoculation methods of Pseudomonas putida on growth and yield of tomato plants. J. Soil Sci. Plant Nutr. [online]. 2017, vol.17, n.4, pp.1003-1012. ISSN 0718-9516. http://dx.doi.org/10.4067/S0718-95162017000400012.. The objective of this study was to determine the efficiency of applying microcapsules and liquid inoculation of three Pseudomonas putida strains on growth and yield of tomato plants in greenhouse where the results showed differences between both treatments. Rhizobacterial strainsFA-8, FA-56, and FA-60 of P. putida, were assessed individually and combined to determine their capacity to produce indoleacetic acid (IAA). The three strains demonstrated the capacity to produce IAAin vitro, of which FA-56 stood out with 23.02 µg mL-1 in the microcapsule treatment with significant increases in plant height, stem diameter, radical volume, dry biomass, fruit yield, and rhizobacterial population (CFU). These responses could have been ...
We have conducted a preliminary exploration of how alternating light/darkness cycles affect the growth pattern of the heterotrophic, plant-colonizing bacterium Pseudomonas putida KT2440. Cultures of this strain grown overnight in liquid medium were spotted on the center of Petri dishes containing rich medium with 1% agar and either Coomassie brilliant blue or Congo red (50 μg/ml). These dyes bind proteins and other extracellular polymeric substances, respectively, and allow direct visualization of surface changes appearing during colony growth. Plates were incubated for 16h in the dark, sealed with Parafilm to avoid excessive desiccation and transferred to a growth chamber with artificial illumination (white, broad spectrum compact fluorescent lamps with a CRI ≈ 82, 3,500K; Ev ≈ 32,000 lux), set at light/darkness cycles of 16 h/8 h, under constant temperature (30 ± 0.3°C). Control plates were kept in the same conditions but wrapped in aluminum foil. In a second set of experiments, plates ...
The catabolism of glutarate in P. aeruginosa PAO1 depends on GcdH, whose expression is under the control of the GcdR transcriptional activator (38). The catabolism of glutarate in E. coli depends on CsiD and LhgO (20). The expression of csiD in E. coli is significantly upregulated during carbon starvation (39). However, the two pathways cooperate in glutarate catabolism in P. putida KT2440 and both GcdH and CsiD are induced during carbon starvation (19). In this study, it was found that two regulators, CsiR and GcdR, control the two pathways described above in P. putida KT2440, respectively. CsiR cannot interact with the gcdH promoter region (Fig. 4C) and has no effect on the transcription of gcdH (Fig. 4A). Similarly, GcdR cannot interact with the csiD promoter region (Fig. 4D) and has no effect on the transcription of csiD (Fig. 4A). In contrast to GcdH, which is present universally in Pseudomonas species, CsiD and LhgO may be acquired via horizontal gene transfer and are sporadically ...
The implementation of novel platform organisms to be used as microbial cell factories in industrial applications is currently the subject of intense research. Ongoing efforts include the adoption of Pseudomonas putida KT2440 variants with a reduced genome as the functional chassis for biotechnological purposes. In these strains, dispensable functions removed include flagellar motility (1.1% of the genome) and a number of open reading frames expected to improve genotypic and phenotypic stability of the cells upon deletion (3.2% of the genome). In this study, two previously constructed multiple-deletion P. putida strains were systematically evaluated as microbial cell factories for heterologous protein production and compared to the parental bacterium (strain KT2440) with regards to several industrially-relevant physiological traits. Energetic parameters were quantified at different controlled growth rates in continuous cultivations and both strains had a higher adenosine triphosphate content, increased
Pseudomonas putida is a Gram-negative, rod-shaped, saprotrophic soil bacterium. Based on 16S rRNA analysis, P. putida was taxonomically confirmed to be a Pseudomonas species (sensu stricto) and placed, along with several other species, in the P. putida group, to which it lends its name. A variety of P. putida, called multiplasmid hydrocarbon-degrading Pseudomonas, is the first patented organism in the world. Because it is a living organism, the patent was disputed and brought before the United States Supreme Court in the historic court case Diamond v. Chakrabarty, which the inventor, Ananda Mohan Chakrabarty, won. It demonstrates a very diverse metabolism, including the ability to degrade organic solvents such as toluene. This ability has been put to use in bioremediation, or the use of microorganisms to biodegrade oil. Use of P. putida is preferable to some other Pseudomonas species capable of such degradation, as it is a safe species of bacteria, unlike P. aeruginosa, for example, which is an ...
Pseudomonas putida is a Gram-negative, rod-shaped, saprotrophic soil bacterium. Based on 16S rRNA analysis, P. putida was taxonomically confirmed to be a pseudomonas species (sensu stricto) and placed, along with several other species, in the P. putida group, to which it lends its name.,ref,{{#invoke:Citation/CS1,citation ,CitationClass=journal }},/ref, A variety of P. putida, called "multi-plasmid hydrocarbon-degrading Pseudomonas," is the first patented organism in the world. Because it is a living organism, the patent was disputed and brought before the United States Supreme Court in the historic court case Diamond v. Chakrabarty which the inventor, Ananda Mohan Chakrabarty, won. It demonstrates a very diverse metabolism, including the ability to degrade organic solvents such as toluene.,ref,{{#invoke:Citation/CS1,citation ,CitationClass=journal }},/ref, This ability has been put to use in bioremediation, or the use of microorganisms to biodegrade oil. Use of P. putida is preferable to some ...
The toluene-degrading and solvent-tolerant strain Pseudomonas putida DOT-T1E was investigated with respect to its suitability and economic efficiency as biocatalyst in aqueous-organic two-phase systems with aliphatic solvents as organic phase (Rojas et al. 2004, chapter 4 and 5) and to its adaptive responses to the solvent decanol. The adaptive changes on the level of cell morphology (chapter 2), membrane fatty acids and permeability (chapter 3), as well as energetics and surface properties (chapter 5) of P. putida DOT-T1E have been investigated in order to ascertain information about the strains suitability for two-phase biotransformation systems (chapter 4). The morphological adaptation to the presence of solvents was observable in changes of the cell size of P. putida DOT-T1E. Those changes were dependent on the cellular activity and occurred only after addition of non-lethal solvent concentrations. The cells reacted to the presence of organic solvents by decreasing the ratio between surface ...
Members of the genus Pseudomonas are characterized by their ability to grow in simple media at the expense of a great variety of organic compounds. They have a strict respiratory metabolism and are motile by one or several polar flagella. They are common inhabitants of soil and water and can also be found on the surfaces of plants and animals. They are are found in nature in a biofilm or in planktonic form. Pseudomonas putida F1 is a versatile environmental isolate (from a polluted creek in Urbana, USA) that is capable of growth on several aromatic hydrocarbons, including benzene, toluene, ethylbenzene and p -cymene. It is chemotactic to aromatic hydrocarbons and chlorinated aliphatic compounds and has the potential for use in bioremediation applications. P. putida F1 is one of the most well-studied aromatic hydrocarbon degrading bacterial strains; over 200 articles have been written about various aspects of P. putida F1 physiology, enzymology, and genetics (adapted from ...
The substance belongs to the category of perylene as indicated by its chemical core structure. Based on this structure and the chemical and biological stability of perylenes under environmental conditions data from structural analogue perylenes are used to support the results of the test substance for this endpoint. The changes in the respiration rate of activated sludge in presence of the analogue perylenes (CAS 4948-15-6, CAS 81-33-4, CAS 128-69-8) were investigated in three guideline studies according to OECD 209 and ISO 8192, respectively, with activated sludge as inoculum. At test termination after 30 minutes effect concentrations , 700 mg/L (nominal) were determined [BASF AG 1998; BASF AG 1999; BASF AG 1986]. Additionally, several oxygen consumption tests which were conducted according to ROBRA (DIN 38412, part 27) are available for the toxicity assessment. The bacteria Pseudomonas putida was exposed to different test concentrations of the following analogue substances: CAS 3049-71-6, CAS ...
Acts on fatty acids from C4 to C11 and on the corresponding 3-hydroxy and 2,3- or 3,4-unsaturated acids. The enzyme from the bacterium Pseudomonas putida also acts on 4-oxo and 4-hydroxy derivatives ...
H-NS family proteins are nucleoid-associated proteins that form oligomers on DNA and function as global regulators. They are found in both bacterial chromosomes and plasmids, and were suggested to be candidate effectors of the interaction between them. TurA and TurB are the predominantly expressed H-NS family proteins encoded on the chromosome of Pseudomonas putida KT2440, while Pmr is encoded on the carbazole-degradative incompatibility group P-7 plasmid pCAR1. Previous transcriptome analyses suggested that they function cooperatively, but play different roles in the global transcriptional network. In addition to differences in protein interaction and DNA-binding functions, cell expression levels are important in clarifying the detailed underlying mechanisms. Here, we determined the precise protein amounts of TurA, TurB, and Pmr in KT2440 in the presence and absence of pCAR1. The intracellular amounts of TurA and TurB in KT2440 and KT2440(pCAR1) were determined by quantitative western blot analysis
PubMed comprises more than 30 million citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.
Bacteria cope with and adapt to stress by modulating gene expression in response to specific environmental cues. In this study the transcriptional response of Pseudomonas putida KT2440 to oxidative, osmotic, and membrane stress conditions at two time points was investigated via identification of differentially expressed mRNAs and sRNAs. A total of 440 small RNA transcripts were detected, where 10% correspond to previously annotated sRNAs, 40% are novel intergenic transcripts and 50% are novel transcripts antisense to annotated genes. Each stress elicits a unique response as far as the extent and dynamics of the transcriptional changes. Nearly 200 protein-encoding genes exhibited significant changes in all stress types, implicating their participation in a general stress response. Almost half of the sRNA transcripts were differentially expressed in at least one condition, suggesting possible functional roles in the cellular response to stress conditions. The data show a higher fraction of differentially
Carbapenems are critically important antimicrobials as a last line of defense against multidrug-resistant Gram-negative bacterial infections (1, 2). As such, the increasing prevalence of carbapenemase-producing isolates in animal husbandry is of great concern. While the metallo-β-lactamase (MBL)-producing bacteria have been commonly identified from food animals (3-7), blaMBL-carrying Pseudomonas spp. are rarely reported in animal husbandry or the surrounding environment. Although we have reported the high prevalence of NDM in Enterobacteriaceae isolates from poultry production in Shandong Province (7), carbapenemase-producing non-Enterobacteriaceae isolates have not been identified in the same region. Here, we report four chromosome-borne VIM-positive Pseudomonas isolates: one Pseudomonas aeruginosa isolate from a swallow (Yanornis martini), one Pseudomonas putida isolate from a fly, and two P. putida isolates from chickens. The blaVIM-2 gene was identified in the P. aeruginosa isolate, but 27 ...
Water supply biofilms have the potential to harbour waterborne diseases, accelerate corrosion, and contribute to the formation of tuberculation in metallic pipes. One particular species of bacteria known to be found in the water supply networks is Pseudomonas sp., with the presence of Pseudomonas putida being isolated to iron pipe tubercles. Current methods for detecting and analysis pipe biofilms are time consuming and expensive. The application of metabolomics techniques could provide an alternative method for assessing biofilm risk more efficiently based on bacterial activity. As such, this paper investigates the application of metabolomic techniques and provides a proof-of-concept application using liquid chromatography coupled with time-of-flight mass spectrometry (LC-ToF-MS) to three biologically independent P. putida samples, across five different growth conditions exposed to solid and soluble iron (Fe). Analysis of the samples in +ESI and -ESI mode yielded 887 and 1789 metabolite ...
If you have used this database, please ensure that you acknowledge this most recent Pseudomonas Genome Database publication rather than just the website URL. Thank you!. Winsor GL, Griffiths EJ, Lo R, Dhillon BK, Shay JA, Brinkman FS (2016 ...
If you have used this database, please ensure that you acknowledge this most recent Pseudomonas Genome Database publication rather than just the website URL. Thank you!. Winsor GL, Griffiths EJ, Lo R, Dhillon BK, Shay JA, Brinkman FS (2016 ...
Plays an important role in the initiation and regulation of chromosomal replication. Binds to the origin of replication; it binds specifically double-stranded DNA at a 9 bp consensus (dnaA box): 5-TTATC[CA]A[CA]A-3. DnaA binds to ATP and to acidic phospholipids.
Ratio of pyoverdines and dihydropyoverdines produced by Pseudomonas putida. BTP16 is influenced by the growth rate of the strain ...
Transcriptional activation of quinoline degradation operons of Pseudomonas putida 86 by the AraC/XylS-type regulator OxoS and cross-regulation of the PqorM promoter by XylS
TY - JOUR. T1 - Crystal structures reveal metal-binding plasticity at the metallo-β-lactamase active site of PqqB from Pseudomonas putida. AU - Tu, Xiongying. AU - Latham, John A.. AU - Klema, Valerie J.. AU - Evans, Robert L.. AU - Li, Chao. AU - Klinman, Judith P.. AU - Wilmot, Carrie M.. PY - 2017/10/1. Y1 - 2017/10/1. N2 - PqqB is an enzyme involved in the biosynthesis of pyrroloquinoline quinone and a distal member of the metallo-β-lactamase (MBL) superfamily. PqqB lacks two residues in the conserved signature motif HxHxDH that makes up the key metal-chelating elements that can bind up to two metal ions at the active site of MBLs and other members of its superfamily. Here, we report crystal structures of PqqB bound to Mn2+, Mg2+, Cu2+, and Zn2+. These structures demonstrate that PqqB can still bind metal ions at the canonical MBL active site. The fact that PqqB can adapt its side chains to chelate a wide spectrum of metal ions with different coordination features on a uniform main chain ...
This research project attempted to grow and purify soluble Pseudomonas putida HMGR (PpHMGR) enzyme for the purpose of experimentation on its hypothesized morpheein protein behavior. Inclusion body formation has been the primary limiting factor in the growth and purification of soluble PpHMGR. Variation on incubation temperature, IPTG concentration, and growth time were explored in the growth phase, and imidazole concentration, presence of DTT, and presence of TCEP were explored in the purification phase. PpHMGR was grown in an E. coli host, cell lysis was performed by sonication, and subsequent purification was performed by nickel column elution FPLC. The purified product was characterized by FPLC, gel electrophoresis, and enzyme kinetics to determine the reduction of inclusion body formation and presence of soluble PpHMGR.
Sensitivity of Pseudomonas putida mutants to heat stress. Overnight-grown cells equivalent to an OD600 unit of 0.6 were mixed with LB broth in a total volume of
Abstract: 从土样中筛选得到一株产羰基还原酶的菌种恶臭假单胞菌(Pseudomonas putida)ZJPH1606,该菌能不对称催化2′-三氟甲基苯乙酮合成(R)-1-(2-三氟甲基苯基)乙醇,对映体过量值超过99.0%.通过单因素考察产酶培养基组成发现:葡萄糖、牛肉膏和MgSO4·7H2 O对酶活的影响较为明显,进一步采用响应面法对产酶培养基进行了优化.结果表明:最优发酵培养基组成为葡萄糖38.5g/L,牛肉膏32.7g/L,MgSO4·7H2O1.1g/L.在最适培养条件下,菌体酶活力达0.31U/g,较优化前提高了71.0%.该研究结果丰富了羰基还原酶数据库的基因序列,为高效合成(R)-1-(2-三氟甲基苯基)乙醇提供了新途径. ...
The test system for the selection of mutants based on creation of functional promoter sequences for the transcriptional activation of the pheBA phenol degradation genes in P. putida enables us to study different types of mutations and transposition of mobile DNA elements. Based on the analysis of the mutants characterized in this study and previously (32), the sequence upstream of the pheBA genes contains many potential −35 and −10 hexamers for promoter creation (Fig. 2). Most of these −35 and −10 elements are located too far from each other, but the distance between the promoter elements can be optimized by deletions.. The length of the deletions between six different −35 hexamers and four different −10 hexamers that created a functional promoter varied from 2 to 80 bp. In some cases, the length of the spacer between the −35 sequence TTGCAC and −10 sequence CATAAT was extended from a nonoptimal 15 bp to the optimal distance (17 or 18 bp) due to 2-bp or 3-bp insertions. ...
BACKGROUND: Pseudomonas putida is a Gram-negative, non-fermenting bacterium frequently encountered in various environmental niches. P. putida rarely causes disease in humans, though serious infections and outbreaks have been reported from time to time. Some have suggested that P. putida functions as an exchange platform for antibiotic resistance genes (ARG), and thus represents a serious concern in the spread of ARGs to more pathogenic organisms within a hospital. Though poorly understood, the frequency of ARG exchange between P. putida and the more virulent Pseudomonas aeruginosa and its clinical relevance are particularly important for designing efficient infection control strategies, such as deciding whether high-risk patients colonized with a multidrug resistant but typically low pathogenic P. putida strain should be contact isolated or not. RESULTS: In this study, 21,373 screening samples (stool, rectal and throat swab) were examined to determine the presence of P. putida in a high-risk ...
The Pm promoter of the TOL plasmid of Pseudomonas putida is expressed at high level along the growth curve. This transcription is dependent on the positive regulator XylS activated by 3-methylbenzoate. The sigma factor sigma 38 is required for expression in early stationary phase and thereafter. To …
The heterologous expression of genes in prokaryotes can be challenging, especially if the genes originate from a distant host or if the source is uncertain, such as a metagenomic expression library. Many vectors have been developed based on broad host range origins of replication, but these tend to focus on either gram(+) or gram(-) prokaryotes. This invention regards the construction of a completely synthetic expression vector, namely pPolyREPII, based on both the pBBR1 (for gram-positive) and pWV01 (for gram-negative) origin of replication, allowing replication in both types of organisms. The expression of pPolyREPII was assessed by cloning the gfp gene with a His6 tag sequence. A strong gfp expression could be observed in various prokaryotes, such as E.coli DH5α, Pseudomonas putida KT2440 and Bacillus subtilis 168. The presence of GFP was confirmed by western blot analysis using antibodies against His6 tag.. ...
2M7B: The Solution Structures of Two Prophage Homologues of the Bacteriophage lambda Ea8.5 Protein Reveal a Newly Discovered Hybrid Homeodomain/Zinc-Finger Fold.
Pseudomonas putida strain ATCC 8209 clone 3 16S ribosomal RNA gene, partial sequence; 16S-23S ribosomal RNA intergenic spacer and tRNA-Glu gene, complete sequence; and 23S ribosomal RNA gene, partial ...
Eesti Teadusinfosüsteem koondab informatsiooni teadus- ja arendusasutuste, teadlaste, teadusprojektide ning erinevate teadustegevuste tulemuste kohta.
For the removal of toxic and recalcitrant organic substances from wastewater, bioaugmentation with bacteria harbouring specific degradation pathways in activate
U83218 Pseudomonas putida MnB1; ATCC 23483 Pseudomonas putida genomic clone transposon-tagged mutant UT6403 similar to 2-oxoglutarate dehydrogenase E1o subunit (sucA), genomic survey ...
Eesti Teadusinfosüsteem koondab informatsiooni teadus- ja arendusasutuste, teadlaste, teadusprojektide ning erinevate teadustegevuste tulemuste kohta.
In this study, we have demonstrated that the activation of transcription from the fusion promoters PRA1 and PLA1 (formed at the junctions of the target DNA with the right end and left end of Tn4652, respectively) is positively affected by IHF inP. putida. The involvement of IHF in the modulation of transcription from the fusion promoters PRA1 and PLA1 was demonstrated by comparing the levels of expression from the fusion promoters in the wild type and in the IHF-negative background of P. putida(Fig. 3). Construction of the P. putida RT31 carrying the genes coding for P. putida IHF under the control of thePtac promoter and the lacIq repressor in its chromosome allowed us to modify the level of IHF expression by changing the concentration of IPTG in the growth medium. The amount of the IHF-specific complex detected in the gel shift assay increased in crude extracts of P. putida RT31 cells grown at higher concentrations of IPTG in the growth medium inducing IHF expression (Fig. 4). The elevated ...