Biomaterial Database

Origin of small beta-lactamase-specifying plasmids in Haemophilus species and Neisseria gonorrhoeae. 1986

J Brunton, and M Meier, and N Erhman, and D Clare, and R Almawy

Fifty-nine percent of unselected strains of Haemophilus parainfluenzae were found to carry small, phenotypically cryptic plasmid DNA species. Using filter blot hybridization, we found several plasmids which were homologous to the small beta-lactamase-specifying plasmids pJB1 and pFA7, which were originally isolated from Haemophilus ducreyi and Neisseria gonorrhoeae, respectively. Detailed filter hybridization studies combined with electron microscope heteroduplex analysis suggested that three cryptic plasmids are completely homologous to the non-TnA sequences of pJB1. One cryptic plasmid was found to be highly homologous to pJB603, a small beta-lactamase plasmid previously found in two isolates of H. influenzae. A second group of plasmids were found to carry sequences homologous to pJB1 and other sequences homologous to pJB603. These results strongly suggest that small beta-lactamase plasmids found in Haemophilus species and N. gonorrhoeae may have arisen by insertion of the transposable beta-lactamase-specifying element TnA into small, phenotypically cryptic replicons resident in H. parainfluenzae. Attempts to reproduce such a recombination event in the laboratory were not successful.

UI	MeSH Term	Description	Entries
D009344	Neisseria gonorrhoeae	A species of gram-negative, aerobic bacteria primarily found in purulent venereal discharges. It is the causative agent of GONORRHEA.	Diplococcus gonorrhoeae,Gonococcus,Gonococcus neisseri,Merismopedia gonorrhoeae,Micrococcus der gonorrhoe,Micrococcus gonococcus,Micrococcus gonorrhoeae
D009692	Nucleic Acid Heteroduplexes	Double-stranded nucleic acid molecules (DNA-DNA or DNA-RNA) which contain regions of nucleotide mismatches (non-complementary). In vivo, these heteroduplexes can result from mutation or genetic recombination; in vitro, they are formed by nucleic acid hybridization. Electron microscopic analysis of the resulting heteroduplexes facilitates the mapping of regions of base sequence homology of nucleic acids.	Heteroduplexes, Nucleic Acid,Heteroduplex DNA,Acid Heteroduplexes, Nucleic,DNA, Heteroduplex
D009693	Nucleic Acid Hybridization	Widely used technique which exploits the ability of complementary sequences in single-stranded DNAs or RNAs to pair with each other to form a double helix. Hybridization can take place between two complimentary DNA sequences, between a single-stranded DNA and a complementary RNA, or between two RNA sequences. The technique is used to detect and isolate specific sequences, measure homology, or define other characteristics of one or both strands. (Kendrew, Encyclopedia of Molecular Biology, 1994, p503)	Genomic Hybridization,Acid Hybridization, Nucleic,Acid Hybridizations, Nucleic,Genomic Hybridizations,Hybridization, Genomic,Hybridization, Nucleic Acid,Hybridizations, Genomic,Hybridizations, Nucleic Acid,Nucleic Acid Hybridizations
D010957	Plasmids	Extrachromosomal, usually CIRCULAR DNA molecules that are self-replicating and transferable from one organism to another. They are found in a variety of bacterial, archaeal, fungal, algal, and plant species. They are used in GENETIC ENGINEERING as CLONING VECTORS.	Episomes,Episome,Plasmid
D011995	Recombination, Genetic	Production of new arrangements of DNA by various mechanisms such as assortment and segregation, CROSSING OVER; GENE CONVERSION; GENETIC TRANSFORMATION; GENETIC CONJUGATION; GENETIC TRANSDUCTION; or mixed infection of viruses.	Genetic Recombination,Recombination,Genetic Recombinations,Recombinations,Recombinations, Genetic
D004251	DNA Transposable Elements	Discrete segments of DNA which can excise and reintegrate to another site in the genome. Most are inactive, i.e., have not been found to exist outside the integrated state. DNA transposable elements include bacterial IS (insertion sequence) elements, Tn elements, the maize controlling elements Ac and Ds, Drosophila P, gypsy, and pogo elements, the human Tigger elements and the Tc and mariner elements which are found throughout the animal kingdom.	DNA Insertion Elements,DNA Transposons,IS Elements,Insertion Sequence Elements,Tn Elements,Transposable Elements,Elements, Insertion Sequence,Sequence Elements, Insertion,DNA Insertion Element,DNA Transposable Element,DNA Transposon,Element, DNA Insertion,Element, DNA Transposable,Element, IS,Element, Insertion Sequence,Element, Tn,Element, Transposable,Elements, DNA Insertion,Elements, DNA Transposable,Elements, IS,Elements, Tn,Elements, Transposable,IS Element,Insertion Element, DNA,Insertion Elements, DNA,Insertion Sequence Element,Sequence Element, Insertion,Tn Element,Transposable Element,Transposable Element, DNA,Transposable Elements, DNA,Transposon, DNA,Transposons, DNA
D004269	DNA, Bacterial	Deoxyribonucleic acid that makes up the genetic material of bacteria.	Bacterial DNA
D006190	Haemophilus	A genus of PASTEURELLACEAE that consists of several species occurring in animals and humans. Its organisms are described as gram-negative, facultatively anaerobic, coccobacillus or rod-shaped, and nonmotile.	Hemophilus
D006193	Haemophilus influenzae	A species of HAEMOPHILUS found on the mucous membranes of humans and a variety of animals. The species is further divided into biotypes I through VIII.	Bacterium influenzae,Coccobacillus pfeifferi,Haemophilus meningitidis,Hemophilus influenzae,Influenza-bacillus,Mycobacterium influenzae
D001618	beta-Lactamases	Enzymes found in many bacteria which catalyze the hydrolysis of the amide bond in the beta-lactam ring. Well known antibiotics destroyed by these enzymes are penicillins and cephalosporins.	beta-Lactamase,beta Lactamase,beta Lactamases