China
Africa
Explore chapters and articles related to this topic
Glossary of scientific and technical terms in bioengineering and biological engineering
Published in Megh R. Goyal, Scientific and Technical Terms in Bioengineering and Biological Engineering, 2018
pBR322 is a plasmid and was one of the first widely used E. coli cloning vectors. The p stands for “plasmid,” and BR for “Bolivar” and “Rodriguez.” pBR322 is 4361 base pairs in length and contains the replicon of plasmid pMB1, the ampR gene, encoding the ampicillin resistance protein (source plasmid RSF2124) and the tetR gene, encoding the tetracycline resistance protein (source plasmid pSC101). The plasmid has unique restriction sites for more than forty restriction enzymes. The 11 of these 40 sites lie within the tetR gene. There are 2 sites for restriction enzymes HindIII and ClaI within the promoter of the tetR gene. There are 6 key restriction sites inside the ampR gene. The ori site in this plasmid is pMB1 (a close relative of ColE1). The circular sequence is numbered such that 0 is the middle of the unique EcoRI site and the count increases through the tet gene. The ampicillin resistance gene is penicillin beta-lactamase. Promoters P1 and P3 are for the beta-lactamase gene. P3 is the natural promoter, and P1 is artificially created by the ligation of two different DNA fragments to create pBR322. P2 is in the same region as P1, but it is on the opposite strand and initiates transcription in the direction of the tetracycline resistance gene.
Selection and Improvement of Industrial Organisms for Biotechnological Applications
Published in Nduka Okafor, Benedict C. Okeke, Modern Industrial Microbiology and Biotechnology, 2017
Nduka Okafor, Benedict C. Okeke
In the early years of genetic engineering, naturally occurring plasmids such as Col E1 and pSC 101 were used as cloning vectors. They were small and had single sites for the common endonucleases. However, they lacked markers which would help select transformed organisms. New plasmids were therefore developed. The best and most commonly used plasmid is pBR322 developed by Francisco Bolivar. (In naming plasmids p is used to show it is a plasmid; p is followed by the initials of the worker who isolated or developed the plasmid; numbers are used to denote the particular strain). Plasmid pBR322 has all the properties expected in a plasmid vector: low molecular weight, two markers (resistance to ampicillin, ApR and tetracycline, TcR), an origin of replication, and several single-cut replication sites (see map of pBR322 in Fig. 7.4). Modifications of the original pBR322 have been made to suit special purposes, and consequently many variants exist in the pBR322 family. A widely used variant of pBR322 is pAT153, which some consider a better vector than its parent because it is present in more copies per cell than pBR322.
Degradation of antibiotic resistance contaminants in wastewater by atmospheric cold plasma: kinetics and mechanisms
Published in Environmental Technology, 2021
Xinyu Liao, Donghong Liu, Shiguo Chen, Xingqian Ye, Tian Ding
In this study, E. coli DH5α was used as the host bacteria for plasmid pBR322. For E. coli preparation, one single colony was transferred into 100 ml of LB medium (50 μg/ml ampicillin and 5 μg/ml tetracycline), followed by an incubation for 16 h at 180 rpm and 37°C to reach stationary growth phase. The E. coli suspension was collected after centrifugation at 2320×g and 4°C for 10 min. The collected precipitates were then washed by sterile phosphate buffer with a pH of 7.0 ± 0.2 for three times. The final concentration of E. coli DH5α stocks was achieved at around 9 log10 CFU/ml. The plasmid pBR322 (4361 bp) was widely used as an E. coli vector, which carried the ampicillin (blaTEM) and tetracycline (tet) resistance genes (Figure S1). The plasmids were extracted and collected with a Minor plasmid kit (Tiangen Biotech Co., Ltd., Shanghai, China) according to the manufacturer’s instructions. The purity and quantity of extracted plasmids were determined by a NanoDrop OneC Microvolume UV-Vis Spectrophotometer (Thermo Fisher Scientific Inc., Waltham, MA, U.S.A.).
A facile approach of tetraaqua-bis[4-(H-tetrazol-5-yl)pyridinato]-zinc(II) dihydrate with their biological activities
Published in Journal of Coordination Chemistry, 2023
Rama Devi Gutta, Abdul Rajack, Satya Veni Sunkara
pBR322 plasmid DNA is used for DNA-cleavage activity. The gel electrophoresis method uses the pBR322 plasmid DNA and the metal complexes. The electrophoresis was run on an agarose gel under an electric field influence at a constant voltage. The sample dissolved in DMSO is taken along with pBR322 plasmid DNA in 0.1 μg/mL in Tris-HCl buffer (0.05 M, pH 7.4). The sample with three concentrations of 1 µL, 2 µL, and 3 µL is taken in lanes. The mixtures are incubated at 37 °C for 2 h, and later the buffer is loaded and moved up to 75% of the gel with a constant voltage (80 V). After completion, the gel is destained and visualized under UV light, and photographs were taken [26].
New cobalt(III) complex with triethylenetetramine and 2,2′-bipyridine: synthesis, crystal structure, DNA interaction, hirshfeld surface, DFT analysis, and cytotoxicity
Published in Inorganic and Nano-Metal Chemistry, 2022
M. N. Arumugham, H. Gopinathan, M. Sumithra, S. Baskaran, R. Kumar, Sadegh Kaviani
All commercially available reagents, such as methanol, anhydrous diethyl ether, Co(Cl)2.5H2O, and 2,2-bipyridine monohydrate, are of analytical grade and should be used exactly as received. Bangalore Genie (India) provided the plasmid pBR322 DNA. Triethylenetetramine and disodium salt of calf thymus DNA (CT-DNA), tris (hydroxymethyl) aminomethane (tris) and ethidium bromide were purchased from Sigma Aldrich.