What is a oriV?

The characteristics of plasmid interaction with the subfraction include the presence of supercoil DNA after extraction, the binding of the origin of plasmid replication (oriV) in vitro, and the association of the two plasmid-encoded initiation (TrfA) proteins (encoded by overlapping genes).

What is oriT genetics?

An origin of transfer (oriT) is a short sequence ranging from 40-500 base pairs in length that is necessary for the transfer of DNA from a gram-negative bacterial donor to recipient during bacterial conjugation.

At which region the plasmid transfer is initiated?

Transfer is initiated at the right border and terminated at the left border and requires the vir genes of the Ti plasmid.

What is RK2 resistant to?

Structure. RK2 is approximately 60 kbp long and contains genes for replication, maintenance, conjugation and antibiotic resistance. The resistance genes confer resistance to the antibiotics kanamycin, ampicillin and tetracycline.

What group does RK2 belong to?

plasmid incompatibility group P
The low-copy number RK2 plasmid belongs to the plasmid incompatibility group P (IncP) of Escherichia coli (IncP-1 of Pseudomonas species). It can persist in most Gram-negative bacteria [8, 9], and is thus referred to as having a broad host range.

What is oriT plasmid?

The origin of transfer (oriT) is the sequence within which conjugal transfer of plasmid DNA is initiated, and is absolutely required in cis for plasmid mobilization.

What does a relaxase do?

A relaxase is a single-strand DNA transesterase enzyme produced by some prokaryotes and viruses. Relaxases are responsible for site- and strand-specific nicks in unwound double-stranded DNA .

What enzyme nicks the F-factor at oriT?

A relaxase, usually encoded by the plasmid, recognizes oriT, makes a single-strand DNA break (a nick) in oriT, and covalently attaches to the 5′ end of the nicked DNA strand via a phosphotyrosyl linkage (9, 34).

Is RK2 self transmissible?

Self-transmissible RK2 plasmid efficiently delivers DNA to bacteria population even in the absence of transconjugant selection. (A) A schematic of a multi-plasmid system comprising CRISPR mobilizable plasmid (pCRISPR) and conjugative helper plasmid (pHELP).

What is RP4 plasmid?

Plasmid RP4 (IncP ) contains two transfer regions designated Tra1 and Tra2, both of which contribute to Mpf. Twelve components are essential for Mpf, TraF of Tra1 and 11 Tra2 proteins, TrbB, -C, -D, -E, -F, -G, -H, -I, -J, -K, and -L. The phenotype of defined mutants in each of the Tra2 genes was determined.

What is IncP plasmid?

IncF plasmids have systems which guarantee their autonomous replication but also encode addiction systems frequently based on toxin-antitoxin factors.

What are HFR strains?

A high-frequency recombination cell (Hfr cell) (also called an Hfr strain) is a bacterium with a conjugative plasmid (for example, the F-factor) integrated into its chromosomal DNA. The integration of the plasmid into the cell’s chromosome is through homologous recombination.

Which enzyme nicks the F-factor at oriT?

A relaxase, usually encoded by the plasmid, recognizes oriT, makes a single-strand DNA break (a nick) in oriT, and covalently attaches to the 5′ end of the nicked DNA strand via a phosphotyrosyl linkage (9, 34)….TABLE 1.

Strain	Genotypea
CAL224	ΔICEBs1-205::kan
CAL264	ICEBs10str-84 amyE::[(Pspank-int) spc] comK::cat

Why is oriT Special to relaxase?

oriT functions in cis and is required for efficient transfer. A relaxase, usually encoded by the plasmid, recognizes oriT, makes a single-strand DNA break (a nick) in oriT, and covalently attaches to the 5′ end of the nicked DNA strand via a phosphotyrosyl linkage (9, 34).

What is oriT in plasmid?

What is the role of relaxase?

What is unusual about the RK2 plasmid?

Plasmid RK2 is unusual in its ability to replicate stably in a wide range of Gram-negative bacteria. The replication origin (oriV) and a plasmid-encoded initiation protein (TrfA; expressed as 33 and 44 kDa forms) are essential for RK2 replication.

How are F plasmid produced?

The F plasmid contains only F factor DNA and no DNA from the bacterial genome. F’ (F-prime) bacteria are formed by incorrect excision from the chromosome, resulting in F plasmid carrying bacterial sequences that are next to where the F episome has been inserted.