scholarly journals Biodegradation of waste greases and biochemical properties of a novel lipase from Pseudomonas synxantha PS1

2016 ◽  
Vol 62 (7) ◽  
pp. 588-599 ◽  
Author(s):  
Xianghai Cai ◽  
Siqi Chen ◽  
Hong Yang ◽  
Wei Wang ◽  
Lin Lin ◽  
...  
Keyword(s):  
Lipase Activity ◽  
Produced Water ◽  
Wild Strain ◽  
Biochemical Properties ◽  
Butyl Alcohol ◽  
Oil Well ◽  
Lipase Gene ◽  
Reading Frame ◽  
16S Rdna Sequence Analysis ◽  
Alkaline Conditions

A lipase-producing bacterial strain was isolated from oil-well-produced water in Shengli oilfield (Shandong province, China) and was identified as Pseudomonas synxantha by 16S rDNA sequence analysis (named Pseudomonas synxantha PS1). Strain PS1 showed a maximum lipase activity of 10.8 U/mL after culturing for 48 h at 30 °C, with lactose (4 g/L) as carbon source, tryptone (8 g/L) as nitrogen source, olive oil (0.5%, v/v) as inductor, and the initial pH 8.0. Meanwhile, the lipase gene from P. synxantha PS1 was cloned and expressed in Escherichia coli BL21 with the vector pET28a. The novel gene (lipPS1) has an open reading frame of 1425 bp and encodes a 474 aa lipase (LipPS1) sharing the most identity (87%) with the lipase in Pseudomonas fluorescens. LipPS1 preferably acted on substrates with a long chain (C10–C18) of fatty acids. The optimum pH and temperature of the recombinant enzyme were 8.0 and 40 °C, respectively, towards the optimum substrate p-nitrophenyl palmitate. The LipPS1 showed remarkable stability under alkaline conditions and was stable at pH 7.0–10.0 (retaining more than 60% activity). From the organic solvents tests, the lipase was activated by 15% (v/v) methanol (112%), 15% ethanol (127%), and 15% n-butyl alcohol (116%). LipPS1 presented strong biodegradability of waste grease; 93% of waste grease was hydrolyzed into fatty acid after 12 h at 30 °C. This is the first report of the lipase activity and lipase gene obtained from P. synxantha (including wild strain and recombinant strain) and of the recombinant LipPS1 with the detailed enzymatic properties. Also a preliminary study of the biodegradability of waste greases shows the potential value in industry applications.

scholarly journals Low-Temperature Lipase from Psychrotrophic Pseudomonas sp. Strain KB700A

2001 ◽  
Vol 67 (9) ◽  
pp. 4064-4069 ◽  
Author(s):  
Naeem Rashid ◽  
Yuji Shimada ◽  
Satoshi Ezaki ◽  
Haruyuki Atomi ◽  
Tadayuki Imanaka
Keyword(s):  
Lipase Activity ◽  
Lipase Gene ◽  
Reading Frame ◽  
Cold Environments ◽  
Dna Library ◽  
Gene Sequence Analysis ◽  
Genomic Dna Library ◽  
Lipase A ◽  
Chain Lengths ◽  
Sigmoidal Growth

ABSTRACT We have previously reported that a psychrotrophic bacterium,Pseudomonas sp. strain KB700A, which displays sigmoidal growth even at −5°C, produced a lipase. A genomic DNA library of strain KB700A was introduced into Escherichia coli TG1, and screening on tributyrin-containing agar plates led to the isolation of the lipase gene. Sequence analysis revealed an open reading frame (KB-lip) consisting of 1,422 nucleotides that encoded a protein (KB-Lip) of 474 amino acids with a molecular mass of 49,924 Da. KB-Lip showed 90% identity with the lipase fromPseudomonas fluorescens and was found to be a member of Subfamily I.3 lipase. Gene expression and purification of the recombinant protein were performed. KB-Lip displayed high lipase activity in the presence of Ca2+. Addition of EDTA completely abolished lipase activity, indicating that KB-Lip was a Ca2+-dependent lipase. Addition of Mn2+ and Sr2+ also led to enhancement of lipase activity but to a much lower extent than that produced by Ca2+. The optimal pH of KB-Lip was 8 to 8.5. The addition of detergents enhanced the enzyme activity. When p-nitrophenyl esters and triglyceride substrates of various chain-lengths were examined, the lipase displayed highest activity towards C10 acyl groups. We also determined the positional specificity and found that the activity was 20-fold higher toward the 1(3) position than toward the 2 position. The optimal temperature for KB-Lip was 35°C, lower than that for any previously reported Subfamily I.3 lipase. The enzyme was also thermolabile compared to these lipases. Furthermore, KB-Lip displayed higher levels of activity at low temperatures than did other enzymes from Subfamily I.3, indicating that KB-Lip has evolved to function in cold environments, in accordance with the temperature range for growth of its psychrotrophic host, strain KB700A.

scholarly journals Isolation of Halophilic Bacteria from Inland Petroleum- Producing Wells

Fine Focus ◽  
2017 ◽  
Vol 3 (2) ◽  
pp. 101-110
Author(s):  
Maedgen Q. Lindsey ◽  
Jennifer R. Huddleston
Keyword(s):  
Salt Tolerance ◽  
Gene Sequence ◽  
Produced Water ◽  
High Salinity ◽  
Halophilic Bacteria ◽  
Optimal Growth ◽  
Oil Well ◽  
Marine Microorganisms ◽  
16S Rdna Gene ◽  
Mannitol Salt Agar

The goals of this study were to isolate microorganisms from oil well-produced water, identify the microorganisms, and test the microorganisms’ salt tolerance. Saltwater collected from two well locations producing from different zones in Jones County, Texas, was spread onto Mannitol Salt Agar (MSA). Isolates showed a 16S rDNA gene sequence identity of 99% with Idiomarina baltica and Marinobacter persicus. Salt tolerance assays indicated an optimal growth concentration of 10-12.5% NaCl for the Idiomarina isolate and a decrease in growth beyond 5% NaCl for the Marinobacter isolate. In conclusion, organisms that are phylogenetically similar to marine microorganisms are present in oil well environments, and have variable salt tolerances, which may prove useful in microbialmediated hydrocarbon bioremediation of high salinity environments.

The extrachromosomal replication of Dictyostelium plasmid Ddp2 requires a cis-acting element and a plasmid-encoded trans-acting factor

1990 ◽  
Vol 10 (7) ◽  
pp. 3727-3736
Author(s):  
B Leiting ◽  
I J Lindner ◽  
A A Noegel
Keyword(s):  
Escherichia Coli ◽  
Copy Number ◽  
Wild Strain ◽  
Open Reading Frame ◽  
Mobility Shift ◽  
Reading Frame ◽  
Cis Acting ◽  
Transformation Vector ◽  
Cis And Trans ◽  
Electrophoretic Mobility Shift Assays

Dictyostelium discoideum plasmid Ddp2 from the wild strain WS380B is a 5.8-kilobase (kb) supercoiled circle with a copy number of 300 per haploid genome. We previously described the construction of an extrachromosomally replicating transformation vector pnDeI carrying 4.7 kb of Ddp2 sequences (B. Leiting, and A. Noegel, Plasmid 20:241-248, 1988). In order to reduce the sequences required for extrachromosomal maintenance in D. discoideum, we characterized Ddp2 by sequence analysis, by deletion experiments, by transcription mapping, by electrophoretic mobility shift assays, and by expression of its single open reading frame in Escherichia coli. Two elements were involved in replication of Ddp2: a cis-acting sequence located on a 592-base-pair (bp) fragment that consisted of 220 bp of essential and 372 bp of auxiliary sequences, and a 2.7-kb open reading frame which most likely encodes a trans-acting factor. The cis- and trans-acting elements did not overlap and were shown to act independently from the location of the sequences encoding the trans-acting factor.

Novel external-loop CO2-lift reactor for desilication of alkaline/surfactant/polymer produced water from oil well

2018 ◽  
Vol 332 ◽  
pp. 66-75 ◽  
Author(s):  
Chao Chen ◽  
Jiahuan Lu ◽  
Wenheng Jing ◽  
Ming Zhou ◽  
Ming Zhu ◽  
...  
Keyword(s):  
Produced Water ◽  
Oil Well ◽  
External Loop ◽  
Alkaline Surfactant Polymer

Screening of Biosurfactant-Producing Thick Oil-Degrading Bacteria and its Degradation Effect

2013 ◽  
Vol 821-822 ◽  
pp. 1027-1030
Author(s):  
Jing Chun Wu ◽  
Xiao Long Zhang ◽  
Yang Zhao ◽  
Liu Yang
Keyword(s):  
Crude Oil ◽  
Produced Water ◽  
Oil Well ◽  
Separation And Purification ◽  
Oil Composition ◽  
Industrial Fermentation ◽  
Degrading Bacteria ◽  
Before And After ◽  
Degradation Effect ◽  
Composition Changes

Four bacterias were separation and purification from oil well produced water of Daqing 9 factory, optimizing two degrading bacterias 17# and 7#. Through fermentation cultivation, observing their growth and metabolism laws and the viscosity of crude oil before and after the action. Results showed that the strains 7# and 17# of thick oil degradation rate were 84.9%, 73.9% respectively. Through the experiment contrasts, give the crude oil composition changes and chromatogram of the strains 7# before and after the action. Finally, choose strains 7# as thick oil-degrading bacteria for industrial fermentation.

scholarly journals Identification of an Active Reverse Transcriptase Enzyme Encoded by a Human Endogenous HERV-K Retrovirus

1999 ◽  
Vol 73 (3) ◽  
pp. 2365-2375 ◽  
Author(s):  
Ben Berkhout ◽  
Maarten Jebbink ◽  
Jozsef Zsíros
Keyword(s):  
Reverse Transcriptase ◽  
Human Genome ◽  
Genetic Recombination ◽  
Biochemical Properties ◽  
Rnase H ◽  
Open Reading Frame ◽  
Biologically Active ◽  
Virus Family ◽  
Reading Frame ◽  
Reverse Transcriptase Enzyme

ABSTRACT Of the numerous endogenous retroviral elements that are present in the human genome, the abundant HERV-K family is distinct because several members are transcriptionally active and coding for biologically active proteins. A detailed phylogeny of the HERV-K family based on the partial sequence of the reverse transcriptase (RT) gene revealed a high incidence of an intact RT open reading frame within the HML-2 subgroup of HERV-K elements. In this study, we report the cloning of six full-length HML-2 RT genes, of which five contain an uninterrupted open reading frame. The RT enzymes were expressed as glutathione S-transferase fusion proteins inEscherichia coli, and several HERV-K RT enzymes demonstrated polymerase as well as RNase H activity. Several biochemical properties of the RT polymerase were analyzed, including the template requirements and optimal reaction conditions (temperature, type of divalent cation). Inspection of the nucleotide sequence of the HERV-K RT genes demonstrated a mosaic structure, suggesting that a high level of genetic recombination has occurred in this virus family, which is a hallmark of replication by means of reverse transcription. The selective pressure to maintain the RT coding potential is illustrated by the sequence of a particular HERV-K isolate that contains three 1-nucleotide deletions within a small RT segment, thus maintaining the open reading frame. These combined results may suggest that these endogenous RT enzymes still have a biological function. It is possible that the RT activity was involved in the spread of this major class of retroelements by retrotransposition, and in fact it cannot be excluded that this retrovirus group is still mobile. The endogenous RT activity may also have been involved in the shaping of the human genome, e.g., by formation of pseudogenes.

scholarly journals DNA intensity and genetic diversity of oil palm (Elaeis guineensis) to determine an elite low lipase line

2021 ◽  
Vol 22 (2) ◽  
Author(s):  
Nina Unzila Angkat ◽  
LUTHFI AZIZ MAHMUD SIREGAR ◽  
Mohammad Basyuni ◽  
Dadang Afandi ◽  
INDRA SYAHPUTRA
Keyword(s):  
Genetic Diversity ◽  
Lipase Activity ◽  
Oil Palm ◽  
Elaeis Guineensis ◽  
Edible Oil ◽  
Lipase Gene ◽  
Analysis Of Molecular Variance ◽  
Expected Heterozygosity ◽  
Activity Groups ◽  
Informative Content

Abstract. Angkat NU, Siregar LAM, Basyuni M, Afandi D, Syahputra I. 2021. DNA intensity and genetic diversity of oil palm (Elaeis guineensis) to determine an elite low lipase line. Biodiversitas 22: 900-905. The acidification of palm oil due to lipase activity in the mesocarp is assessed under genetic control. Three molecular markers have been established to gauge the lipase gene in oil palm. Lower lipase activity is desired for good quality edible oil. This study aims to identify the genetic diversity by screening groups/families to determine an elite low lipase genotype of oil palm. Genetic diversity and population structure of 15 groups of oil palm were investigated by using three specific markers with GenAlex 6.502 software. Results show that the Polymorphic Informative Content (PIC) value of markers was around 0,985-0,993, which indicates that these markers are effective in determining the diversity of lipase activity in oil palm. Analysis of molecular variance (AMOVA) revealed that genetic diversity varies within individuals (54%), among individuals (31%), and among population (15%). The value of number of alleles (Na), number of effective alleles (Ne), observed heterozygosity (Ho), expected heterozygosity (He), and number of allele migration (Nm) indicate that the genetic diversity in this population is relatively low. Phylogenetic analysis identified two main groups as high lipase and low lipase activity groups based on DNA intensity.

Geochemical Techniques to Detect Sources of Fluids in Highly Pressured Casing-Casing Annuli CCA

2021 ◽  
Author(s):  
Dr. Peter Birkle ◽  
Hamdi A. AlRamadan
Keyword(s):  
Produced Water ◽  
Environmental Isotopes ◽  
Late Triassic ◽  
Drilling Fluids ◽  
Fluid Identification ◽  
Water Composition ◽  
Alkaline Conditions ◽  
Alteration Processes ◽  
Mud Filtrate ◽  
Supply Water

Abstract The buildup of high casing-casing annulus (CCA) pressure compromises the well integrity and can lead to serious incidents if left untreated. Potential sources of water causing the elevated CCA pressure are either trapped water in the cement column or water from a constant feeding source. This study utilizes inorganic geochemical techniques to determine the provenance of CCA produced water as trigger for high pressure in newly drilled wells. Affinities in the hydrochemical (major, minor and trace elements) and stable isotopic (δ2H, δ18O) composition are monitored to identify single fluid types, multi-component mixing and secondary fluid alteration processes. As a proof-of-concept, geochemical fingerprints of CCA produced water from three wells were correlated with potential source candidates, i.e., utilized drilling fluids (mud filtrate, supply water) from the target well site, Early - Late Cretaceous aquifers and Late Jurassic - Late Triassic formation waters from adjacent wells and fields. Geochemical affinities of CCA water with groundwater from an Early Cretaceous aquifer postulate the presence one single horizon for active water inflow. Non-reactive elements (Na, Cl) and environmental isotopes (δ2H, δ18O) were found to be most suited tools for fluid identification. 2H/1H and 18O/16O ratios of supply water and mud filtrate are close to global meteoric water composition, whereas formation waters are enriched in 18O. Elevated SO4 and K concentrations and extreme alkaline conditions for CCA water indicates the occurrence of minor secondary alteration processes, such the contact of inflowing groundwater with cement or fluid mixing with minor portions of KCl additives. The presented technology in this study enables the detection of high CCA pressure and fluid leakages sources, thereby allowing workover engineers to plan for potential remedial actions prior to moving the rig to the affected well; hence significantly reducing operational costs. Appropriate remedial solutions can be prompted for safe well abandonment as well as to resume operation at the earliest time.

scholarly journals Identification and Analysis of a Novel Heparin-Binding Glycoprotein Encoded by Human Herpesvirus 7

2000 ◽  
Vol 74 (10) ◽  
pp. 4530-4540 ◽  
Author(s):  
David Skrincosky ◽  
Peter Hocknell ◽  
Linda Whetter ◽  
Paola Secchiero ◽  
Bala Chandran ◽  
...  
Keyword(s):  
Viral Genome ◽  
Neutralizing Antibodies ◽  
Specific Interaction ◽  
Human Herpesvirus ◽  
Sucrose Density Gradient ◽  
Biochemical Properties ◽  
Heparin Binding ◽  
Cdna Insert ◽  
Reading Frame ◽  
Viral Attachment

ABSTRACT Human herpesvirus 6 (HHV-6) and HHV-7 are closely related betaherpesviruses that encode a number of genes with no known counterparts in other herpesviruses. The product of one such gene is the HHV-6 glycoprotein gp82-105, which is a major virion component and a target for neutralizing antibodies. A 1.7-kb cDNA clone from HHV-7 was identified which contains a large open reading frame capable of encoding a predicted primary translational product of 468 amino acids (54 kDa) with 13 cysteine residues and 9 potential N-linked glycosylation sites. This putative protein, which we have termed gp65, was homologous to HHV-6 gp105 (30% identity) and contained a single potential membrane-spanning domain located near its amino terminus. Comparison of the cDNA sequence with that of the viral genome revealed that the gene encoding gp65 contains eight exons, spanning almost 6 kb of the viral genome at the right (3′) end of the HHV-7 genome. Northern (RNA) blot analysis with poly(A)+ RNA from HHV-7-infected cells revealed that the cDNA insert hybridized to a single major RNA species of 1.7 kb. Antiserum raised against a purified, recombinant form of gp65 recognized a protein of roughly 65 kDa in sucrose density gradient-purified HHV-7 preparations; treatment with PNGase F reduced this glycoprotein to a putative precursor of approximately 50 kDa. Gp65-specific antiserum also neutralized the infectivity of HHV-7, while matched preimmune serum did not do so. Finally, analysis of the biochemical properties of recombinant gp65 revealed a specific interaction with heparin and heparan sulfate proteoglycans and not with closely related molecules such as N-acetylheparin and de-N-sulfated heparin. At least two domains of the protein were found to contribute to heparin binding. Taken together, these findings suggest that HHV-7 gp65 may contribute to viral attachment to cell surface proteoglycans.

Sign in / Sign up

Export Citation Format

Share Document