A unit transposon carries a core transposition module, which can be mainly divided into Tn3 1, Tn7 2, 3 and Tn554 4 families. Each family can be further divided into various subfamilies based on the amino acid sequences of transposases. The Tn3-family core transposition module is composed of the transposase and resolvase genes and a resolution (res) site. A Tn7-family transposon typically encodes the core transposition determents TnsA (endonuclease), TnsB (transposase), TnsC (transposition regulator), and TnsD plus TnsE (target-site selection proteins), and uses a "cut-and-paste" transposition mechanism. Tn3- and Tn7-family transposons have terminal IRL/IRR pairs. A Tn554-family transposon encodes multiple transposases and transposes preferentially to a single chromosomal site (e.g. att554 for Tn554), generating flanking DRs (e.g. GATGTA for Tn554), but it carries no IRL/IRR pairs.
The transposase sequences of indicated transposons were aligned using Clustal Omega 1.2.2 5. A maximum-likelihood tree was constructed using MEGA X 10.1.8 6 with a bootstrap iteration of 500. Shown in the tree are a total of 94 representative Tn3-family transposons, which are derived from a previous grouping scheme 1, and 49 of them are included in REMED.
The transposase sequences of indicated transposons were aligned using Clustal Omega 1.2.2 5. A maximum-likelihood tree was constructed using MEGA X 10.1.8 6 with a bootstrap iteration of 500. Shown in the tree are a total of 13 representative Tn7-family transposons, which are based on a previous grouping scheme 7, and all of them are included in REMED.
The transposase (TnpA or GinA) sequences of indicated transposons were aligned using Clustal Omega 1.2.2 5. A maximum-likelihood tree was constructed using MEGA X 10.1.8 6 with a bootstrap iteration of 500. Shown in the tree are a total of 10 representative Tn554-family transposons, and four (Tn554, Tn5406, Tn6488 and Tn6571) of them are included in REMED.
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