1
|
Mohamed AR, Ochsenkühn MA, Kazlak AM, Moustafa A, Amin SA. The coral microbiome: towards an understanding of the molecular mechanisms of coral-microbiota interactions. FEMS Microbiol Rev 2023; 47:fuad005. [PMID: 36882224 PMCID: PMC10045912 DOI: 10.1093/femsre/fuad005] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 02/10/2023] [Accepted: 02/15/2023] [Indexed: 03/09/2023] Open
Abstract
Corals live in a complex, multipartite symbiosis with diverse microbes across kingdoms, some of which are implicated in vital functions, such as those related to resilience against climate change. However, knowledge gaps and technical challenges limit our understanding of the nature and functional significance of complex symbiotic relationships within corals. Here, we provide an overview of the complexity of the coral microbiome focusing on taxonomic diversity and functions of well-studied and cryptic microbes. Mining the coral literature indicate that while corals collectively harbour a third of all marine bacterial phyla, known bacterial symbionts and antagonists of corals represent a minute fraction of this diversity and that these taxa cluster into select genera, suggesting selective evolutionary mechanisms enabled these bacteria to gain a niche within the holobiont. Recent advances in coral microbiome research aimed at leveraging microbiome manipulation to increase coral's fitness to help mitigate heat stress-related mortality are discussed. Then, insights into the potential mechanisms through which microbiota can communicate with and modify host responses are examined by describing known recognition patterns, potential microbially derived coral epigenome effector proteins and coral gene regulation. Finally, the power of omics tools used to study corals are highlighted with emphasis on an integrated host-microbiota multiomics framework to understand the underlying mechanisms during symbiosis and climate change-driven dysbiosis.
Collapse
Affiliation(s)
- Amin R Mohamed
- Biology Program, New York University Abu Dhabi, Abu Dhabi 129188, United Arab Emirates
| | - Michael A Ochsenkühn
- Biology Program, New York University Abu Dhabi, Abu Dhabi 129188, United Arab Emirates
| | - Ahmed M Kazlak
- Systems Genomics Laboratory, American University in Cairo, New Cairo 11835, Egypt
- Biotechnology Graduate Program, American University in Cairo, New Cairo 11835, Egypt
| | - Ahmed Moustafa
- Systems Genomics Laboratory, American University in Cairo, New Cairo 11835, Egypt
- Biotechnology Graduate Program, American University in Cairo, New Cairo 11835, Egypt
- Department of Biology, American University in Cairo, New Cairo 11835, Egypt
| | - Shady A Amin
- Biology Program, New York University Abu Dhabi, Abu Dhabi 129188, United Arab Emirates
- Center for Genomics and Systems Biology (CGSB), New York University Abu Dhabi, Abu Dhabi 129188, United Arab Emirates
| |
Collapse
|
2
|
Ushijima B, Saw JH, Videau P, Häse CC. Comparison of Vibrio coralliilyticus virulence in Pacific oyster larvae and corals. MICROBIOLOGY (READING, ENGLAND) 2022; 168. [PMID: 35380530 DOI: 10.1099/mic.0.001169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The bacterium Vibrio coralliilyticus has been implicated in mass mortalities of corals and shellfish larvae. However, using corals for manipulative infection experiments can be logistically difficult compared to other model organisms, so we aimed to establish oyster larvae infections as a proxy model. Therefore, this study assessed the virulence of six wild-type V. coralliilyticus strains, and mutants of one strain with deletions of known virulence factors, between Pacific oyster larvae (Crassostrea gigas) and Hawaiian rice coral (Montipora capitata) infection systems. The wild-type strains tested displayed variable virulence in each system, but virulence levels between hosts were not necessarily comparable. Strains RE98 and OCN008 maintained a medium to high level of virulence across hosts and appeared to be more generalist pathogens. Strain H1, in contrast, was avirulent towards coral but displayed a medium level of virulence towards oyster larvae. Interestingly, the BAA-450 type strain had a medium level of virulence towards coral and was the least virulent to oyster larvae. A comparison of known virulence factors determined that the flagellum, motility or chemotaxis, all of which play a significant role in coral infections, were not crucial for oyster infections with strain OCN008. A genomic comparison of the newly sequenced strain H1 with the other strains tested identified 16 genes potentially specific to coral pathogens that were absent in H1. This is both the first comparison of various V. coralliilyticus strains across infection systems and the first investigation of a strain that is non-virulent to coral. Our results indicate that the virulence of V. coralliilyticus strains in coral is not necessarily indicative of virulence in oyster larvae, and that the set of genes tested are not required for virulence in both model systems. This study increases our understanding of the virulence between V. coralliilyticus strains and helps assess their potential threat to marine environments and shellfish industries.
Collapse
Affiliation(s)
- Blake Ushijima
- Department of Biology and Marine Biology, University of North Carolina Wilmington, Wilmington, NC, USA
| | - Jimmy H Saw
- Department of Biological Sciences, The George Washington University, Washington, DC, USA
| | - Patrick Videau
- Department of Biology, Southern Oregon University, Ashland, OR, USA
- Present address: Bayer Crop Science, MO, Chesterfield, USA
| | - Claudia C Häse
- Carlson College of Veterinary Medicine, Oregon State University, Corvallis, OR, USA
| |
Collapse
|
3
|
Bacteriophages against Vibrio coralliilyticus and Vibrio tubiashii: Isolation, Characterization, and Remediation of Larval Oyster Mortalities. Appl Environ Microbiol 2021; 87:AEM.00008-21. [PMID: 33674441 DOI: 10.1128/aem.00008-21] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Accepted: 02/24/2021] [Indexed: 12/31/2022] Open
Abstract
Vibrio coralliilyticus and Vibrio tubiashii are pathogens responsible for high larval oyster mortality rates in shellfish hatcheries. Bacteriophage therapy was evaluated to determine its potential to remediate these mortalities. Sixteen phages against V. coralliilyticus and V. tubiashii were isolated and characterized from Hawaiian seawater. Fourteen isolates were members of the Myoviridae family, and two were members of the Siphoviridae In proof-of-principle trials, a cocktail of five phages reduced mortalities of larval Eastern oysters (Crassostrea virginica) and Pacific oysters (Crassostrea gigas) by up to 91% 6 days after challenge with lethal doses of V. coralliilyticus Larval survival depended on the oyster species, the quantities of phages and vibrios applied, and the species and strain of Vibrio A later-generation cocktail, designated VCP300, was formulated with three lytic phages subsequently named Vibrio phages vB_VcorM-GR7B, vB_VcorM-GR11A, and vB_VcorM-GR28A (abbreviated 7B, 11A, and 28A, respectively). Together, these three phages displayed host specificity toward eight V. coralliilyticus strains and a V. tubiashii strain. Larval C. gigas mortalities from V. coralliilyticus strains RE98 and OCN008 were significantly reduced by >90% (P < 0.0001) over 6 days with phage treatment compared to those of untreated controls. Genomic sequencing of phages 7B, 11A, and 28A revealed 207,758-, 194,800-, and 154,046-bp linear DNA genomes, respectively, with the latter showing 92% similarity to V. coralliilyticus phage YC, a strain from the Great Barrier Reef, Australia. Phage 7B and 11A genomes showed little similarity to phages in the NCBI database. This study demonstrates the promising potential for phage therapy to reduce larval oyster mortalities in oyster hatcheries.IMPORTANCE Shellfish hatcheries encounter episodic outbreaks of larval oyster mortalities, jeopardizing the economic stability of hatcheries and the commercial shellfish industry. Shellfish pathogens like Vibrio coralliilyticus and Vibrio tubiashii have been recognized as major contributors of larval oyster mortalities in U.S. East and West Coast hatcheries for many years. This study isolated, identified, and characterized bacteriophages against these Vibrio species and demonstrated their ability to reduce mortalities from V. coralliilyticus in larval Pacific oysters and from both V. coralliilyticus and V. tubiashii in larval Eastern oysters. Phage therapy offers a promising approach for stimulating hatchery production to ensure the well-being of hatcheries and the commercial oyster trade.
Collapse
|
4
|
Ushijima B, Meyer JL, Thompson S, Pitts K, Marusich MF, Tittl J, Weatherup E, Reu J, Wetzell R, Aeby GS, Häse CC, Paul VJ. Disease Diagnostics and Potential Coinfections by Vibrio coralliilyticus During an Ongoing Coral Disease Outbreak in Florida. Front Microbiol 2020; 11:569354. [PMID: 33193161 PMCID: PMC7649382 DOI: 10.3389/fmicb.2020.569354] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 10/06/2020] [Indexed: 01/24/2023] Open
Abstract
A deadly coral disease outbreak has been devastating the Florida Reef Tract since 2014. This disease, stony coral tissue loss disease (SCTLD), affects at least 22 coral species causing the progressive destruction of tissue. The etiological agents responsible for SCTLD are unidentified, but pathogenic bacteria are suspected. Virulence screens of 400 isolates identified four potentially pathogenic strains of Vibrio spp. subsequently identified as V. coralliilyticus. Strains of this species are known coral pathogens; however, cultures were unable to consistently elicit tissue loss, suggesting an opportunistic role. Using an improved immunoassay, the VcpA RapidTest, a toxic zinc-metalloprotease produced by V. coralliilyticus was detected on 22.3% of diseased Montastraea cavernosa (n = 67) and 23.5% of diseased Orbicella faveolata (n = 24). VcpA+ corals had significantly higher mortality rates and faster disease progression. For VcpA- fragments, 21.6% and 33.3% of M. cavernosa and O. faveolata, respectively, died within 21 d of observation, while 100% of similarly sized VcpA+ fragments of both species died during the same period. Further physiological and genomic analysis found no apparent differences between the Atlantic V. coralliilyticus strains cultured here and pathogens from the Indo-Pacific but highlighted the diversity among strains and their immense genetic potential. In all, V. coralliilyticus may be causing coinfections that exacerbate existing SCTLD lesions, which could contribute to the intraspecific differences observed between colonies. This study describes potential coinfections contributing to SCTLD virulence as well as diagnostic tools capable of tracking the pathogen involved, which are important contributions to the management and understanding of SCTLD.
Collapse
Affiliation(s)
- Blake Ushijima
- Smithsonian Marine Station, Fort Pierce, FL, United States
| | - Julie L Meyer
- Soil and Water Sciences Department, University of Florida, Gainesville, FL, United States
| | | | - Kelly Pitts
- Smithsonian Marine Station, Fort Pierce, FL, United States
| | | | - Jessica Tittl
- Soil and Water Sciences Department, University of Florida, Gainesville, FL, United States
| | | | - Jacqueline Reu
- Smithsonian Marine Station, Fort Pierce, FL, United States
| | - Raquel Wetzell
- Smithsonian Marine Station, Fort Pierce, FL, United States
| | - Greta S Aeby
- Smithsonian Marine Station, Fort Pierce, FL, United States
| | - Claudia C Häse
- Carlson College of Veterinary Medicine, Oregon State University, Corvallis, OR, United States
| | - Valerie J Paul
- Smithsonian Marine Station, Fort Pierce, FL, United States
| |
Collapse
|
5
|
Kim HJ, Jun JW, Giri SS, Chi C, Yun S, Kim SG, Kim SW, Han SJ, Kwon J, Oh WT, Lee SB, Kim JH, Park SC. Identification and Genome Analysis of Vibrio coralliilyticus Causing Mortality of Pacific Oyster ( Crassostrea gigas) Larvae. Pathogens 2020; 9:E206. [PMID: 32168754 PMCID: PMC7157721 DOI: 10.3390/pathogens9030206] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 03/08/2020] [Accepted: 03/09/2020] [Indexed: 01/23/2023] Open
Abstract
Vibrio coralliilyticus is known as a coral pathogen that also infects marine bivalve larvae worldwide. It is considered to be one of the major constraints in artificial marine bivalve seed production as it causes mortality. In this study, we first isolated and characterized a high virulent of V. coralliilyticus designated as SNUTY-1 that was the cause of Pacific oyster larvae mortality in Korea. In the pathogenicity test, exposure to 2.14 × 105 CFU/mL for 24 h caused mortality to 88.65 ± 2.4% of the tested healthy Pacific oyster larvae. SNUTY-1 showed anti-microbial resistance to β-lactams, such as penicillins, cephalosporins, and carbapenems. We sequenced and assembled the complete genome of SNUTY-1 (5,842,676 bp), consisting of two chromosomes (Chr I and Chr II) and two plasmids (pSNUTY1 and pSNUTY2). The COG functional analysis confirmed that Chr I had more genes associated with basic cellular functions in comparison to Chr II. The results of the phylogenetic trees based on OrthoANI values indicated that the SNUTY-1 was closely related to V. coralliilyticus strains. SNUTY-1 had a unique plasmid (pSNUTY2), which could mean that the Korean isolate is different from other sequenced V. coralliilyticus strains from different geographical origins. Toxic proteins such as cytolysin/hemolysin and extracellular metalloprotease genes were encoded on Chr I and Chr II of SNUTY-1. These data facilitate the control of V. coralliilyticus infections in aquaculture by providing valuable insights into the biodiversity of this organism and valuable information for the study of virulence factors.
Collapse
Affiliation(s)
- Hyoun Joong Kim
- Laboratory of Aquatic Biomedicine, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul 08826, Korea; (H.J.K.); (S.S.G.); (S.Y.); (S.G.K.); (S.W.K.); (S.J.H.); (J.K.); (W.T.O.); (S.B.L.)
| | - Jin Woo Jun
- Department of Aquaculture, Korea National College of Agriculture and Fisheries, Jeonju 54874, Korea;
| | - Sib Sankar Giri
- Laboratory of Aquatic Biomedicine, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul 08826, Korea; (H.J.K.); (S.S.G.); (S.Y.); (S.G.K.); (S.W.K.); (S.J.H.); (J.K.); (W.T.O.); (S.B.L.)
| | - Cheng Chi
- Laboratory of Aquatic Nutrition and Ecology, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, China;
| | - Saekil Yun
- Laboratory of Aquatic Biomedicine, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul 08826, Korea; (H.J.K.); (S.S.G.); (S.Y.); (S.G.K.); (S.W.K.); (S.J.H.); (J.K.); (W.T.O.); (S.B.L.)
| | - Sang Guen Kim
- Laboratory of Aquatic Biomedicine, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul 08826, Korea; (H.J.K.); (S.S.G.); (S.Y.); (S.G.K.); (S.W.K.); (S.J.H.); (J.K.); (W.T.O.); (S.B.L.)
| | - Sang Wha Kim
- Laboratory of Aquatic Biomedicine, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul 08826, Korea; (H.J.K.); (S.S.G.); (S.Y.); (S.G.K.); (S.W.K.); (S.J.H.); (J.K.); (W.T.O.); (S.B.L.)
| | - Se Jin Han
- Laboratory of Aquatic Biomedicine, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul 08826, Korea; (H.J.K.); (S.S.G.); (S.Y.); (S.G.K.); (S.W.K.); (S.J.H.); (J.K.); (W.T.O.); (S.B.L.)
| | - Jun Kwon
- Laboratory of Aquatic Biomedicine, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul 08826, Korea; (H.J.K.); (S.S.G.); (S.Y.); (S.G.K.); (S.W.K.); (S.J.H.); (J.K.); (W.T.O.); (S.B.L.)
| | - Woo Taek Oh
- Laboratory of Aquatic Biomedicine, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul 08826, Korea; (H.J.K.); (S.S.G.); (S.Y.); (S.G.K.); (S.W.K.); (S.J.H.); (J.K.); (W.T.O.); (S.B.L.)
| | - Sung Bin Lee
- Laboratory of Aquatic Biomedicine, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul 08826, Korea; (H.J.K.); (S.S.G.); (S.Y.); (S.G.K.); (S.W.K.); (S.J.H.); (J.K.); (W.T.O.); (S.B.L.)
| | - Ji Hyung Kim
- Infectious Disease Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 34141, Korea
| | - Se Chang Park
- Laboratory of Aquatic Biomedicine, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul 08826, Korea; (H.J.K.); (S.S.G.); (S.Y.); (S.G.K.); (S.W.K.); (S.J.H.); (J.K.); (W.T.O.); (S.B.L.)
| |
Collapse
|
6
|
Bustamante D, Segarra S, Tortajada M, Ramón D, del Cerro C, Auxiliadora Prieto M, Iglesias JR, Rojas A. In silico prospection of microorganisms to produce polyhydroxyalkanoate from whey: Caulobacter segnis DSM 29236 as a suitable industrial strain. Microb Biotechnol 2019; 12:487-501. [PMID: 30702206 PMCID: PMC6465232 DOI: 10.1111/1751-7915.13371] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 12/20/2018] [Accepted: 12/26/2018] [Indexed: 11/29/2022] Open
Abstract
Polyhydroxyalkanoates (PHAs) are polyesters of microbial origin that can be synthesized by prokaryotes from noble sugars or lipids and from complex renewable substrates. They are an attractive alternative to conventional plastics because they are biodegradable and can be produced from renewable resources, such as the surplus of whey from dairy companies. After an in silico screening to search for ß-galactosidase and PHA polymerase genes, several bacteria were identified as potential PHA producers from whey based on their ability to hydrolyse lactose. Among them, Caulobacter segnis DSM 29236 was selected as a suitable strain to develop a process for whey surplus valorization. This microorganism accumulated 31.5% of cell dry weight (CDW) of poly(3-hydroxybutyrate) (PHB) with a titre of 1.5 g l-1 in batch assays. Moreover, the strain accumulated 37% of CDW of PHB and 9.3 g l-1 in fed-batch mode of operation. This study reveals this species as a PHA producer and experimentally validates the in silico bioprospecting strategy for selecting microorganisms for waste re-valorization.
Collapse
Affiliation(s)
- Daniel Bustamante
- Biopolis, S.L. Parque Científico Universidad de Valenciaedf. 2 C/Catedrático Agustín Escardino, 946980PaternaValenciaSpain
| | - Silvia Segarra
- Biopolis, S.L. Parque Científico Universidad de Valenciaedf. 2 C/Catedrático Agustín Escardino, 946980PaternaValenciaSpain
| | - Marta Tortajada
- Biopolis, S.L. Parque Científico Universidad de Valenciaedf. 2 C/Catedrático Agustín Escardino, 946980PaternaValenciaSpain
| | - Daniel Ramón
- Biopolis, S.L. Parque Científico Universidad de Valenciaedf. 2 C/Catedrático Agustín Escardino, 946980PaternaValenciaSpain
| | - Carlos del Cerro
- Microbial and Plant Biotechnology DepartmentCentro de Investigaciones BiológicasMadridSpain
- Present address:
National Renewable Energy Laboratory (NREL)15013 Denver West ParkwayGoldenCO80401USA
| | | | - José Ramón Iglesias
- Corporación Alimentaria Peñasanta (CAPSA) Polígono Industrial0, 33199Granda, AsturiasSpain
| | - Antonia Rojas
- Biopolis, S.L. Parque Científico Universidad de Valenciaedf. 2 C/Catedrático Agustín Escardino, 946980PaternaValenciaSpain
| |
Collapse
|
7
|
Miura N, Motone K, Takagi T, Aburaya S, Watanabe S, Aoki W, Ueda M. Ruegeria sp. Strains Isolated from the Reef-Building Coral Galaxea fascicularis Inhibit Growth of the Temperature-Dependent Pathogen Vibrio coralliilyticus. MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2019; 21:1-8. [PMID: 30194504 DOI: 10.1007/s10126-018-9853-1] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 08/23/2018] [Indexed: 06/08/2023]
Abstract
The coral microbiome has attracted increased attention because of its potential roles in host protection against deadly diseases. However, little is known about the role of coral-associated bacteria against the temperature-dependent opportunistic pathogen Vibrio coralliilyticus. In this study, we tested whether bacteria associated with the reef-building coral Galaxea fascicularis could inhibit the growth of V. coralliilyticus. Twenty-nine cultivable bacteria were successfully isolated from a healthy colony of G. fascicularis kept in an aquarium. Among the bacterial isolates, three Ruegeria sp. strains inhibited the growth of V. coralliilyticus P1 as a reference strain and Vibrio sp. isolated in this study. Ruegeria sp. strains were also detected from other G. fascicularis colonies in the aquarium and in previous field studies by 16S rRNA amplicon sequencing, suggesting that Ruegeria sp. strains are common among G. fascicularis colonies. These results illuminate the potential role of Ruegeria sp. in protecting corals against pathogenic Vibrio species.
Collapse
Affiliation(s)
- Natsuko Miura
- Graduate School of Agriculture, Kyoto University, Kyoto, 606-8502, Japan.
- Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Sakai, 599-8531, Japan.
| | - Keisuke Motone
- Graduate School of Agriculture, Kyoto University, Kyoto, 606-8502, Japan
- Japan Society for the Promotion of Science, Tokyo, Japan
| | - Toshiyuki Takagi
- Japan Society for the Promotion of Science, Tokyo, Japan
- Atmosphere and Ocean Research Institute, The University of Tokyo, Kashiwa, 277-8564, Japan
| | - Shunsuke Aburaya
- Graduate School of Agriculture, Kyoto University, Kyoto, 606-8502, Japan
- Japan Society for the Promotion of Science, Tokyo, Japan
| | - Sho Watanabe
- Graduate School of Agriculture, Kyoto University, Kyoto, 606-8502, Japan
| | - Wataru Aoki
- Graduate School of Agriculture, Kyoto University, Kyoto, 606-8502, Japan
| | - Mitsuyoshi Ueda
- Graduate School of Agriculture, Kyoto University, Kyoto, 606-8502, Japan
| |
Collapse
|
8
|
Influence of Chemotaxis and Swimming Patterns on the Virulence of the Coral Pathogen Vibrio coralliilyticus. J Bacteriol 2018; 200:JB.00791-17. [PMID: 29555697 DOI: 10.1128/jb.00791-17] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Accepted: 03/11/2018] [Indexed: 02/08/2023] Open
Abstract
Chemotaxis, the directed movement toward or away from a chemical signal, can be essential to bacterial pathogens for locating hosts or avoiding hostile environments. The coral pathogen Vibrio coralliilyticus chemotaxes toward coral mucus; however, chemotaxis has not been experimentally demonstrated to be important for virulence. To further examine this, in-frame mutations were constructed in genes predicted to be important for V. coralliilyticus chemotaxis. Most Vibrio genomes contain multiple homologs of various chemotaxis-related genes, and two paralogs of each for cheB, cheR, and cheA were identified. Based on single mutant analyses, the paralogs cheB2, cheR2, and cheA1 were essential for chemotaxis in laboratory assays. As predicted, the ΔcheA1 and ΔcheR2 strains had a smooth-swimming pattern, while the ΔcheB2 strain displayed a zigzag pattern when observed under light microscopy. However, these mutants, unlike the parent strain, were unable to chemotax toward the known attractants coral mucus, dimethylsulfoniopropionate, and N-acetyl-d-glucosamine. The ΔcheB2 strain and an aflagellate ΔfliG1 strain were avirulent to coral, while the ΔcheA1 and ΔcheR2 strains were hypervirulent (90 to 100% infection within 14 h on average) compared to the wild-type strain (66% infection within 36 h on average). Additionally, the ΔcheA1 and ΔcheR2 strains appeared to better colonize coral fragments than the wild-type strain. These results suggest that although chemotaxis may be involved with infection (the ΔcheB2 strain was avirulent), a smooth-swimming phenotype is important for bacterial colonization and infection. This study provides valuable insight into understanding V. coralliilyticus pathogenesis and how this pathogen may be transmitted between hosts.IMPORTANCE Corals are responsible for creating the immense structures that are essential to reef ecosystems; unfortunately, pathogens like the bacterium Vibrio coralliilyticus can cause fatal infections of reef-building coral species. However, compared to related human pathogens, the mechanisms by which V. coralliilyticus initiates infections and locates new coral hosts are poorly understood. This study investigated the effects of chemotaxis, the directional swimming in response to chemical signals, and bacterial swimming patterns on infection of the coral Montipora capitata Infection experiments with different mutant strains suggested that a smooth-swimming pattern resulted in hypervirulence. These results demonstrate that the role of chemotaxis in coral infection may not be as straightforward as previously hypothesized and provide valuable insight into V. coralliilyticus pathogenesis.
Collapse
|
9
|
Three Draft Genome Sequences of Vibrio coralliilyticus Strains Isolated from Bivalve Hatcheries. GENOME ANNOUNCEMENTS 2017; 5:5/41/e01162-17. [PMID: 29025954 PMCID: PMC5637514 DOI: 10.1128/genomea.01162-17] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Reported here are the genome sequences of three Vibrio coralliilyticus isolates RE87, AIC-7, and 080116A. Each strain was isolated in association with oyster larvae in commercial aquaculture systems. These draft genomes will be useful for further studies in understanding the genomic features contributing to V. coralliilyticus pathogenicity.
Collapse
|
10
|
Complete Genome Sequence of Vibrio coralliilyticus 58, Isolated from Pacific Oyster ( Crassostrea gigas) Larvae. GENOME ANNOUNCEMENTS 2017; 5:5/23/e00437-17. [PMID: 28596395 PMCID: PMC5465614 DOI: 10.1128/genomea.00437-17] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We report here the complete genome of Vibrio coralliilyticus strain 58, which was originally isolated from inactive Pacific oyster (Crassostrea gigas) larvae in Japan. The assembled genome consisted of two chromosomes and one plasmid. These data will provide valuable information and important insights into the biodiversity of this organism.
Collapse
|
11
|
Carlos C, Pereira LB, Ottoboni LMM. Comparative genomics of Paracoccus sp. SM22M-07 isolated from coral mucus: insights into bacteria-host interactions. Curr Genet 2016; 63:509-518. [PMID: 27796486 DOI: 10.1007/s00294-016-0658-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 10/17/2016] [Indexed: 10/20/2022]
Abstract
One of the main goals of coral microbiology is to understand the ways in which coral-bacteria associations are established and maintained. This work describes the sequencing of the genome of Paracoccus sp. SM22M-07 isolated from the mucus of the endemic Brazilian coral species Mussismilia hispida. Comparative analysis was used to identify unique genomic features of SM22M-07 that might be involved in its adaptation to the marine ecosystem and the nutrient-rich environment provided by coral mucus, as well as in the establishment and strengthening of the interaction with the host. These features included genes related to the type IV protein secretion system, erythritol catabolism, and succinoglycan biosynthesis. We experimentally confirmed the production of succinoglycan by Paracoccus sp. SM22M-07 and we hypothesize that it may be involved in the association of the bacterium with coral surfaces.
Collapse
Affiliation(s)
- Camila Carlos
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, 53703, USA.
| | - Letícia Bianca Pereira
- Center for Molecular Biology and Genetic Engineering (CBMEG), State University of Campinas (UNICAMP), C. P. 6010, Campinas, SP, 13083-875, Brazil
| | - Laura Maria Mariscal Ottoboni
- Center for Molecular Biology and Genetic Engineering (CBMEG), State University of Campinas (UNICAMP), C. P. 6010, Campinas, SP, 13083-875, Brazil
| |
Collapse
|
12
|
Ushijima B, Videau P, Poscablo D, Stengel JW, Beurmann S, Burger AH, Aeby GS, Callahan SM. Mutation of the toxR or mshA genes from Vibrio coralliilyticus strain OCN014 reduces infection of the coral Acropora cytherea. Environ Microbiol 2016; 18:4055-4067. [PMID: 27348808 DOI: 10.1111/1462-2920.13428] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Accepted: 06/19/2016] [Indexed: 01/09/2023]
Abstract
Thermal stress increases the incidence of coral disease, which is predicted to become more common with climate change, even on pristine reefs such as those surrounding Palmyra Atoll in the Northern Line Islands that experience minimal anthropogenic stress. Here we describe a strain of Vibrio coralliilyticus, OCN014, which was isolated from Acropora cytherea during an outbreak of Acropora white syndrome (AWS), a tissue loss disease that infected 25% of the A. cytherea population at Palmyra Atoll in 2009. OCN014 recreated signs of disease in experimentally infected corals in a temperature-dependent manner. Genes in OCN014 with expression levels positively correlated with temperature were identified using a transposon-mediated genetic screen. Mutant strains harbouring transposon insertions in two such genes, toxR (a toxin regulator) and mshA (the 11th gene of the 16-gene mannose-sensitive hemagglutinin (MSHA) type IV pilus operon), had reduced infectivity of A. cytherea. Deletion of toxR and the MSHA operon in a second strain of V. coralliilyticus, OCN008, that induces acute Montipora white syndrome in a temperature-independent manner had similarly reduced virulence. This work provides a link between temperature-dependent expression of virulence factors in a pathogen and infection of its coral host.
Collapse
Affiliation(s)
- Blake Ushijima
- Department of Microbiology, University of Hawai'i at Mānoa, Honolulu, HI, 96822, USA.,Hawai'i Institute of Marine Biology, Kāne'ohe, HI, 96744, USA
| | - Patrick Videau
- Department of Microbiology, University of Hawai'i at Mānoa, Honolulu, HI, 96822, USA.,Department of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Corvallis, OR, 97331, USA
| | - Donna Poscablo
- Department of Microbiology, University of Hawai'i at Mānoa, Honolulu, HI, 96822, USA.,Department of Biology, San Francisco State University, San Francisco, CA, 94132, USA
| | - John W Stengel
- Department of Microbiology, University of Hawai'i at Mānoa, Honolulu, HI, 96822, USA
| | - Silvia Beurmann
- Department of Microbiology, University of Hawai'i at Mānoa, Honolulu, HI, 96822, USA.,Hawai'i Institute of Marine Biology, Kāne'ohe, HI, 96744, USA
| | - Andrew H Burger
- Department of Microbiology, University of Hawai'i at Mānoa, Honolulu, HI, 96822, USA.,Hawai'i Institute of Marine Biology, Kāne'ohe, HI, 96744, USA
| | - Greta S Aeby
- Hawai'i Institute of Marine Biology, Kāne'ohe, HI, 96744, USA
| | - Sean M Callahan
- Department of Microbiology, University of Hawai'i at Mānoa, Honolulu, HI, 96822, USA
| |
Collapse
|
13
|
In Silico Analysis of a Novel Plasmid from the Coral Pathogen Vibrio coralliilyticus Reveals Two Potential "Ecological Islands". Microorganisms 2016; 4:microorganisms4010003. [PMID: 27681896 PMCID: PMC5029508 DOI: 10.3390/microorganisms4010003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Revised: 12/01/2015] [Accepted: 12/10/2015] [Indexed: 11/29/2022] Open
Abstract
As virulence often correlates with the presence of plasmid replicons in several Vibrio spp., this study investigated whether non-chromosomal DNA could be found in the coral pathogen, Vibrio coralliilyticus BAA-450. A circular plasmid, 26,631 bp in size, was identified. DNA sequence analysis indicated that the plasmid contained 30 open reading frames, six tRNA genes, 12 inverted repeats, three direct repeats and presented no continuous sequence identity to other replicons within the database. Consequently, these findings indicate that this is a novel, previously unidentified, plasmid. Two putative “ecological islands” were also identified and are predicted to encode for various factors that would facilitate growth and survival under different ecological conditions. In addition, two open reading frames may encode proteins that contribute to the pathogenicity of the organism. Functional cooperativity is also indicated between several plasmid- and chromosomally-encoded proteins, which, in a single instance, would allow a fully functioning nutrient uptake system to be established.
Collapse
|
14
|
From cholera to corals: Viruses as drivers of virulence in a major coral bacterial pathogen. Sci Rep 2015; 5:17889. [PMID: 26644037 PMCID: PMC4672265 DOI: 10.1038/srep17889] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Accepted: 11/09/2015] [Indexed: 12/20/2022] Open
Abstract
Disease is an increasing threat to reef-building corals. One of the few identified pathogens of coral disease is the bacterium Vibrio coralliilyticus. In Vibrio cholerae, infection by a bacterial virus (bacteriophage) results in the conversion of non-pathogenic strains to pathogenic strains and this can lead to cholera pandemics. Pathogenicity islands encoded in the V. cholerae genome play an important role in pathogenesis. Here we analyse five whole genome sequences of V. coralliilyticus to examine whether virulence is similarly driven by horizontally acquired elements. We demonstrate that bacteriophage genomes encoding toxin genes with homology to those found in pathogenic V. cholerae are integrated in V. coralliilyticus genomes. Virulence factors located on chromosomal pathogenicity islands also exist in some strains of V. coralliilyticus. The presence of these genetic signatures indicates virulence in V. coralliilyticus is driven by prophages and other horizontally acquired elements. Screening for pathogens of coral disease should target conserved regions in these elements.
Collapse
|