Identification of a putative novel polycyclic aromatic hydrocarbon-biodegrading gene cluster in a marine Roseobacteraceae bacterium Sagittula sp. MA-2

ABSTRACT The ability to biodegrade polycyclic aromatic hydrocarbons (PAHs) and the catabolic enzymes responsible for PAH biotransformation in marine bacteria belonging to the family Roseobacteraceae remain largely unexplored despite their wide distribution and highly diverse physiological traits. A...

Full description

Saved in:
Bibliographic Details
Main Authors: Mayuko Abe, Miharu Sakai, Robert A. Kanaly, Jiro F. Mori
Format: Article
Language:English
Published: American Society for Microbiology 2025-01-01
Series:Microbiology Spectrum
Subjects:
Online Access:https://journals.asm.org/doi/10.1128/spectrum.01074-24
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1841556131405627392
author Mayuko Abe
Miharu Sakai
Robert A. Kanaly
Jiro F. Mori
author_facet Mayuko Abe
Miharu Sakai
Robert A. Kanaly
Jiro F. Mori
author_sort Mayuko Abe
collection DOAJ
description ABSTRACT The ability to biodegrade polycyclic aromatic hydrocarbons (PAHs) and the catabolic enzymes responsible for PAH biotransformation in marine bacteria belonging to the family Roseobacteraceae remain largely unexplored despite their wide distribution and highly diverse physiological traits. A bacterial isolate within Roseobacteraceae originating from coastal seawater, Sagittula sp. strain MA-2, that biotransformed phenanthrene and utilized it as a growth substrate was found to possess a putative PAH-degrading gene cluster on one of the eight circular plasmids in its genome. Subsequent comprehensive investigations utilizing bacterial genomes in public databases revealed that gene clusters potentially homologous to this newly found cluster are widely but heterogeneously distributed within Roseobacteraceae and a few non-Roseobacteraceae (Paracoccaceae and Rhizobiaceae) strains from saline environments. Catabolic functions of the enzymes encoded in strain MA-2 were predicted through the profiling of phenanthrene biotransformation products by liquid chromatography-electrospray ionization high-resolution mass spectrometry and substrate docking simulations using predicted three-dimensional structures of selected proteins, and phenanthrene biodegradation pathways were proposed. Strain MA-2 appeared to biodegrade phenanthrene via two separated, concurrent pathways, namely the salicylate and phthalate pathways. This study serves as the first investigation into the functional genes potentially responsible for PAH biodegradation conserved in Roseobacteraceae bacteria, expanding scientific understanding of the physiological repertoire evolved in this ubiquitous marine bacterial group.IMPORTANCEThe ocean is often characterized as the terminal destination for persistent polycyclic aromatic hydrocarbon (PAH) environmental pollutants; however, the ability to biodegrade PAHs and the corresponding enzymes conserved among marine bacteria are less understood compared to their terrestrial counterparts. A marine bacterial isolate, Sagittula sp. strain MA-2, belonging to the family Roseobacteraceae—a widely distributed and physiologically diverse marine bacterial group—was found to possess a functional gene cluster encoding enzymes potentially responsible for PAH biodegradation in its genome and exhibit the ability to biodegrade the three-ring PAH, phenanthrene. Intriguingly, gene clusters potentially homologous to this cluster were also distributed broadly across genomes from different Roseobacteraceae genera in public databases, which has not been previously investigated. The knowledge provided here expands our understanding of the physiology of Roseobacteraceae and may be applied to explore biotechnologically useful bacteria that contribute to the remediation of polluted marine environments or high-salinity wastewater.
format Article
id doaj-art-f0c219355f15478ba550316df92b8801
institution Kabale University
issn 2165-0497
language English
publishDate 2025-01-01
publisher American Society for Microbiology
record_format Article
series Microbiology Spectrum
spelling doaj-art-f0c219355f15478ba550316df92b88012025-01-07T14:05:18ZengAmerican Society for MicrobiologyMicrobiology Spectrum2165-04972025-01-0113110.1128/spectrum.01074-24Identification of a putative novel polycyclic aromatic hydrocarbon-biodegrading gene cluster in a marine Roseobacteraceae bacterium Sagittula sp. MA-2Mayuko Abe0Miharu Sakai1Robert A. Kanaly2Jiro F. Mori3Graduate School of Nanobioscience, Yokohama City University, Yokohama, JapanGraduate School of Nanobioscience, Yokohama City University, Yokohama, JapanGraduate School of Nanobioscience, Yokohama City University, Yokohama, JapanGraduate School of Nanobioscience, Yokohama City University, Yokohama, JapanABSTRACT The ability to biodegrade polycyclic aromatic hydrocarbons (PAHs) and the catabolic enzymes responsible for PAH biotransformation in marine bacteria belonging to the family Roseobacteraceae remain largely unexplored despite their wide distribution and highly diverse physiological traits. A bacterial isolate within Roseobacteraceae originating from coastal seawater, Sagittula sp. strain MA-2, that biotransformed phenanthrene and utilized it as a growth substrate was found to possess a putative PAH-degrading gene cluster on one of the eight circular plasmids in its genome. Subsequent comprehensive investigations utilizing bacterial genomes in public databases revealed that gene clusters potentially homologous to this newly found cluster are widely but heterogeneously distributed within Roseobacteraceae and a few non-Roseobacteraceae (Paracoccaceae and Rhizobiaceae) strains from saline environments. Catabolic functions of the enzymes encoded in strain MA-2 were predicted through the profiling of phenanthrene biotransformation products by liquid chromatography-electrospray ionization high-resolution mass spectrometry and substrate docking simulations using predicted three-dimensional structures of selected proteins, and phenanthrene biodegradation pathways were proposed. Strain MA-2 appeared to biodegrade phenanthrene via two separated, concurrent pathways, namely the salicylate and phthalate pathways. This study serves as the first investigation into the functional genes potentially responsible for PAH biodegradation conserved in Roseobacteraceae bacteria, expanding scientific understanding of the physiological repertoire evolved in this ubiquitous marine bacterial group.IMPORTANCEThe ocean is often characterized as the terminal destination for persistent polycyclic aromatic hydrocarbon (PAH) environmental pollutants; however, the ability to biodegrade PAHs and the corresponding enzymes conserved among marine bacteria are less understood compared to their terrestrial counterparts. A marine bacterial isolate, Sagittula sp. strain MA-2, belonging to the family Roseobacteraceae—a widely distributed and physiologically diverse marine bacterial group—was found to possess a functional gene cluster encoding enzymes potentially responsible for PAH biodegradation in its genome and exhibit the ability to biodegrade the three-ring PAH, phenanthrene. Intriguingly, gene clusters potentially homologous to this cluster were also distributed broadly across genomes from different Roseobacteraceae genera in public databases, which has not been previously investigated. The knowledge provided here expands our understanding of the physiology of Roseobacteraceae and may be applied to explore biotechnologically useful bacteria that contribute to the remediation of polluted marine environments or high-salinity wastewater.https://journals.asm.org/doi/10.1128/spectrum.01074-24RoseobacteraceaeSagittulapolycyclic aromatic hydrocabonsbiodegradationcomparative genomics
spellingShingle Mayuko Abe
Miharu Sakai
Robert A. Kanaly
Jiro F. Mori
Identification of a putative novel polycyclic aromatic hydrocarbon-biodegrading gene cluster in a marine Roseobacteraceae bacterium Sagittula sp. MA-2
Microbiology Spectrum
Roseobacteraceae
Sagittula
polycyclic aromatic hydrocabons
biodegradation
comparative genomics
title Identification of a putative novel polycyclic aromatic hydrocarbon-biodegrading gene cluster in a marine Roseobacteraceae bacterium Sagittula sp. MA-2
title_full Identification of a putative novel polycyclic aromatic hydrocarbon-biodegrading gene cluster in a marine Roseobacteraceae bacterium Sagittula sp. MA-2
title_fullStr Identification of a putative novel polycyclic aromatic hydrocarbon-biodegrading gene cluster in a marine Roseobacteraceae bacterium Sagittula sp. MA-2
title_full_unstemmed Identification of a putative novel polycyclic aromatic hydrocarbon-biodegrading gene cluster in a marine Roseobacteraceae bacterium Sagittula sp. MA-2
title_short Identification of a putative novel polycyclic aromatic hydrocarbon-biodegrading gene cluster in a marine Roseobacteraceae bacterium Sagittula sp. MA-2
title_sort identification of a putative novel polycyclic aromatic hydrocarbon biodegrading gene cluster in a marine roseobacteraceae bacterium sagittula sp ma 2
topic Roseobacteraceae
Sagittula
polycyclic aromatic hydrocabons
biodegradation
comparative genomics
url https://journals.asm.org/doi/10.1128/spectrum.01074-24
work_keys_str_mv AT mayukoabe identificationofaputativenovelpolycyclicaromatichydrocarbonbiodegradinggeneclusterinamarineroseobacteraceaebacteriumsagittulaspma2
AT miharusakai identificationofaputativenovelpolycyclicaromatichydrocarbonbiodegradinggeneclusterinamarineroseobacteraceaebacteriumsagittulaspma2
AT robertakanaly identificationofaputativenovelpolycyclicaromatichydrocarbonbiodegradinggeneclusterinamarineroseobacteraceaebacteriumsagittulaspma2
AT jirofmori identificationofaputativenovelpolycyclicaromatichydrocarbonbiodegradinggeneclusterinamarineroseobacteraceaebacteriumsagittulaspma2