Disruption of hmgA by DNA Duplication is Responsible for Hyperpigmentation in a Vibrio anguillarum Strain

Abstract Vibrio anguillarum 531A, isolated from a diseased fish in the Atlantic Ocean, is a mixture composed of about 95 and 5% of highly pigmented cells (strain 531Ad) and cells with normal levels of pigmentation (strain 531Ac), respectively. Analysis of the V. anguillarum 531Ad DNA region encompas...

Full description

Saved in:
Bibliographic Details
Main Authors: Veronica Batallones, Jennifer Fernandez, Brett Farthing, Jordan Shoemaker, Keizen Li Qian, Kimberly Phan, Eric Fung, Ashley Rivera, Kevin Van, Francesca de la Cruz, Alexandra J. Ferreri, Krystle Burinski, Jackie Zhang, Vicente Lizarraga, Kevin Doan, Kenneth Rocha, German Traglia, Maria S. Ramirez, Marcelo E. Tolmasky
Format: article
Language:EN
Published: Nature Portfolio 2019
Subjects:
R
Q
Online Access:https://doaj.org/article/3335bd8de0424e7a8b235ad9d0c0b6f0
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Abstract Vibrio anguillarum 531A, isolated from a diseased fish in the Atlantic Ocean, is a mixture composed of about 95 and 5% of highly pigmented cells (strain 531Ad) and cells with normal levels of pigmentation (strain 531Ac), respectively. Analysis of the V. anguillarum 531Ad DNA region encompassing genes involved in the tyrosine metabolism showed a 410-bp duplication within the hmgA gene that results in a frameshift and early termination of translation of the homogentisate 1,2-dioxygenase. We hypothesized that this mutation results in accumulation of homogentisate that is oxidized and polymerized to produce pyomelanin. Introduction in E. coli of recombinant clones carrying the V. anguillarum hppD (4-hydroxyphenylpyruvate-dioxygenase), and a mutated hmgA produced brown colored colonies. Complementation with a recombinant clone harboring hmgA restored the original color to the colonies confirming that in the absence of homogentisate 1,2-dioxygenase the intermediary in tyrosine catabolism homogentisate accumulates and undergoes nonenzymatic oxidation and polymerization resulting in high amounts of the brown pigment. Whole-genome sequence analysis showed that V. anguillarum 531 Ac and 531Ad differ in the hmgA gene mutation and 23 mutations, most of which locate to intergenic regions and insertion sequences.