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Girard L, Lood C, De Mot R, van Noort V, Baudart J. Genomic diversity and metabolic potential of marine Pseudomonadaceae. Front Microbiol 2023; 14:1071039. [PMID: 37168120 PMCID: PMC10165715 DOI: 10.3389/fmicb.2023.1071039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2022] [Accepted: 02/21/2023] [Indexed: 05/13/2023] Open
Abstract
Recent changes in the taxonomy of the Pseudomonadaceae family have led to the delineation of three new genera (Atopomonas, Halopseudomonas and Stutzerimonas). However, the genus Pseudomonas remains the most densely populated and displays a broad genetic diversity. Pseudomonas are able to produce a wide variety of secondary metabolites which drives important ecological functions and have a great impact in sustaining their lifestyles. While soilborne Pseudomonas are constantly examined, we currently lack studies aiming to explore the genetic diversity and metabolic potential of marine Pseudomonas spp. In this study, 23 Pseudomonas strains were co-isolated with Vibrio strains from three marine microalgal cultures and rpoD-based phylogeny allowed their assignment to the Pseudomonas oleovorans group (Pseudomonas chengduensis, Pseudomonas toyotomiensis and one new species). We combined whole genome sequencing on three selected strains with an inventory of marine Pseudomonas genomes to assess their phylogenetic assignations and explore their metabolic potential. Our results revealed that most strains are incorrectly assigned at the species level and half of them do not belong to the genus Pseudomonas but instead to the genera Halopseudomonas or Stutzerimonas. We highlight the presence of 26 new species (Halopseudomonas (n = 5), Stutzerimonas (n = 7) and Pseudomonas (n = 14)) and describe one new species, Pseudomonas chaetocerotis sp. nov. (type strain 536T = LMG 31766T = DSM 111343T). We used genome mining to identify numerous BGCs coding for the production of diverse known metabolites (i.e., osmoprotectants, photoprotectants, quorum sensing molecules, siderophores, cyclic lipopeptides) but also unknown metabolites (e.g., ARE, hybrid ARE-DAR, siderophores, orphan NRPS gene clusters) awaiting chemical characterization. Finally, this study underlines that marine environments host a huge diversity of Pseudomonadaceae that can drive the discovery of new secondary metabolites.
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Affiliation(s)
- Léa Girard
- Centre of Microbial and Plant Genetics, KU Leuven, Leuven, Belgium
- Léa Girard,
| | - Cédric Lood
- Centre of Microbial and Plant Genetics, KU Leuven, Leuven, Belgium
- Department of Biosystems, Laboratory of Gene Technology, KU Leuven, Leuven, Belgium
| | - René De Mot
- Centre of Microbial and Plant Genetics, KU Leuven, Leuven, Belgium
| | - Vera van Noort
- Centre of Microbial and Plant Genetics, KU Leuven, Leuven, Belgium
- Institute of Biology, Leiden University, Leiden, Netherlands
| | - Julia Baudart
- Laboratoire de Biodiversité et Biotechnologie Microbiennes, Sorbonne Université, CNRS, Observatoire Océanologique, Banyuls-sur-Mer, France
- *Correspondence: Julia Baudart,
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2
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Yasir M, Khan R, Ullah R, Bibi F, Khan I, Mustafa Karim A, Al-Ghamdi AK, Azhar EI. Bacterial diversity and the antimicrobial resistome in the southwestern highlands of Saudi Arabia. Saudi J Biol Sci 2022; 29:2138-2147. [PMID: 35531257 PMCID: PMC9072880 DOI: 10.1016/j.sjbs.2021.11.047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 11/06/2021] [Accepted: 11/17/2021] [Indexed: 11/24/2022] Open
Abstract
Soil is a reservoir of microbial diversity and the most supportive habitat for acquiring and transmitting antimicrobial resistance. Resistance transfer usually occurs from animal to soil and vice versa, and it may ultimately appear in clinical pathogens. In this study, the southwestern highlands of Saudi Arabia were studied to assess the bacterial diversity and antimicrobial resistance that could be affected by the continuous development of tourism in the region. Such effects could have a long-lasting impact on the local environment and community. Culture-dependent, quantitative polymerase chain reaction (qPCR), and shotgun sequencing-based metagenomic approaches were used to evaluate the diversity, functional capabilities, and antimicrobial resistance of bacteria isolated from collected soil samples. Bacterial communities in the southwestern highlands were mainly composed of Proteobacteria, Bacteroidetes, and Actinobacteria. A total of 102 antimicrobial resistance genes (ARGs) and variants were identified in the soil microbiota and were mainly associated with multidrug resistance, followed by macrolide, tetracycline, glycopeptide, bacitracin, and beta-lactam antibiotic resistance. The mechanisms of resistance included efflux, antibiotic target alteration, and antibiotic inactivation. qPCR confirmed the detection of 18 clinically important ARGs. In addition, half of the 49 identified isolates were phenotypically resistant to at least one of the 15 antibiotics tested. Overall, ARGs and indicator genes of anthropogenic activities (human-mitochondrial [hmt] gene and integron-integrase [int1]) were found in relatively lower abundance. Along with a high diversity of bacterial communities, variation was observed in the relative abundance of bacterial taxa among sampling sites in the southwestern highlands of Saudi Arabia.
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Affiliation(s)
- Muhammad Yasir
- Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah 21589, Saudi Arabia.,Medical Laboratory Technology Department, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Raees Khan
- Department of Biological Sciences, National University of Medical Sciences, Rawalpindi, Pakistan
| | - Riaz Ullah
- Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Fehmida Bibi
- Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah 21589, Saudi Arabia.,Medical Laboratory Technology Department, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Imran Khan
- Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah 21589, Saudi Arabia.,State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Macau S.A.R
| | - Asad Mustafa Karim
- Department of Bioscience and Biotechnology, The University of Suwon, Hwaseong City, Gyeonggi-do, Republic of Korea
| | - Ahmed K Al-Ghamdi
- Medical Laboratory Technology Department, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Esam I Azhar
- Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah 21589, Saudi Arabia.,Medical Laboratory Technology Department, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah 21589, Saudi Arabia
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3
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Ansari MI, Calleja MLI, Silva L, Viegas M, Ngugi DK, Huete-Stauffer TM, Morán XAG. High-Frequency Variability of Bacterioplankton in Response to Environmental Drivers in Red Sea Coastal Waters. Front Microbiol 2022; 13:780530. [PMID: 35432231 PMCID: PMC9009512 DOI: 10.3389/fmicb.2022.780530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Accepted: 03/03/2022] [Indexed: 11/13/2022] Open
Abstract
Autotrophic and heterotrophic bacterioplankton are essential to the biogeochemistry of tropical ecosystems. However, the processes that govern their dynamics are not well known. We provide here a high-frequency assessment of bacterial community dynamics and concurrent environmental factors in Red Sea coastal waters. Weekly sampling of surface samples during a full annual cycle at an enclosed station revealed high variability in ecological conditions, which reflected in changes of major bacterioplankton communities. Temperature varied between 23 and 34°C during the sampling period. Autotrophic (Synechococcus, 1.7–16.2 × 104 cells mL−1) and heterotrophic bacteria (1.6–4.3 × 105 cells mL−1) showed two maxima in abundance in spring and summer, while minima were found in winter and autumn. Heterotrophic cells with high nucleic acid content (HNA) peaked in July, but their contribution to the total cell counts (35–60%) did not show a clear seasonal pattern. Actively respiring cells (CTC+) contributed between 4 and 51% of the total number of heterotrophic bacteria, while live cells (with intact membrane) consistently accounted for over 90%. Sequenced 16S rRNA amplicons revealed a predominance of Proteobacteria in summer and autumn (>40%) and a smaller contribution in winter (21–24%), with members of the Alphaproteobacteria class dominating throughout the year. The contribution of the Flavobacteriaceae family was highest in winter (21%), while the Rhodobacteraceae contribution was lowest (6%). Temperature, chlorophyll-a, and dissolved organic carbon concentration were the environmental variables with the greatest effects on bacterial abundance and diversity patterns.
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Affiliation(s)
- Mohd Ikram Ansari
- Division of Biological and Environmental Sciences and Engineering (BESE), Red Sea Research Center (RSRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
- Department of Biosciences, Integral University, Lucknow, India
- *Correspondence: Mohd Ikram Ansari, ; Xosé Anxelu G. Morán,
| | - Maria LI. Calleja
- Division of Biological and Environmental Sciences and Engineering (BESE), Red Sea Research Center (RSRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
- Department of Climate Geochemistry, Max Planck Institute for Chemistry (MPIC), Mainz, Germany
| | - Luis Silva
- Division of Biological and Environmental Sciences and Engineering (BESE), Red Sea Research Center (RSRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Miguel Viegas
- Division of Biological and Environmental Sciences and Engineering (BESE), Red Sea Research Center (RSRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - David Kamanda Ngugi
- Division of Biological and Environmental Sciences and Engineering (BESE), Red Sea Research Center (RSRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
- Department of Microorganisms, Leibniz Institute DSMZ - German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Tamara Megan Huete-Stauffer
- Division of Biological and Environmental Sciences and Engineering (BESE), Red Sea Research Center (RSRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Xosé Anxelu G. Morán
- Division of Biological and Environmental Sciences and Engineering (BESE), Red Sea Research Center (RSRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
- Centro Oceanográfico de Gijón/Xixón (IEO, CSIC), Gijón/Xixón, Spain
- *Correspondence: Mohd Ikram Ansari, ; Xosé Anxelu G. Morán,
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Chun SJ, Cui Y, Baek SH, Ahn CY, Oh HM. Seasonal succession of microbes in different size-fractions and their modular structures determined by both macro- and micro-environmental filtering in dynamic coastal waters. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 784:147046. [PMID: 33894601 DOI: 10.1016/j.scitotenv.2021.147046] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 04/06/2021] [Accepted: 04/06/2021] [Indexed: 05/16/2023]
Abstract
Microbes interact with each other in response to various environmental changes in coastal marine ecosystems. To explore how the macroenvironment (environmental filtering) and species-engineered microenvironment (niche construction) affect the ecological network of the marine microbiome in the highly dynamic coastal waters of Korea, we analyzed the modular structures of the microbial community and identified microbial interconnections in different size fractions for a year. Fluctuations in the macroenvironment, such as temperature and nutrient concentrations driven by seasonal changes, are the major factors in determining successive microbial modules. Compared to particle-associated (PA) microbes, free-living (FL) microbes seemed to be more affected by macroenvironmental filtering. Modules related to nutrients were further divided into various modules according to different lifestyles. In addition, a large transient discharge of the Changjiang (Yangtze River) in summer also formed a distinct microbial module, which was related to the high ammonia concentration arising from phytoplankton degradation. Microbes belonging to the SAR11, SAR86, and SAR116 clades, Flavobacteriaceae, and MG IIa-L showed repeated interconnections in temperature-related modules, while the SAR202 clade, Marinimicrobia, DEV007 clade, and Arctic97B-4 and Sva0996 marine groups displayed repeated connections in nutrient-related modules. These 'skeleton'-forming microbes created species-engineered microenvironments, further fine-tuning microbial modular structures. Furthermore, they serve as keystone species for module stability by linking interdependent microbial partners within their own modules through universally beneficial metabolic activities. Therefore, they could reinforce the ecological resilience of microbial communities under abiotic and biotic perturbations in dynamic coastal waters. In conclusion, both macro- and micro-environmental filtering were important for determining the seasonal succession of microbial community structures.
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Affiliation(s)
- Seong-Jun Chun
- LMO Research Team, National Institute of Ecology, 1210 Geumgang-ro, Maseo-myeon, Seocheon 33657, Republic of Korea; Cell Factory Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - Yingshun Cui
- Cell Factory Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - Seung Ho Baek
- South Sea Institute, Korea Institute of Ocean Science & Technology, Geoje 53201, Republic of Korea
| | - Chi-Yong Ahn
- Cell Factory Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea; Department of Environmental Biotechnology, KRIBB School of Biotechnology, Korea University of Science and Technology (UST), 217 Gajeong-ro, Yuseong-gu, Daejeon 34113, Republic of Korea.
| | - Hee-Mock Oh
- Cell Factory Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea; Department of Environmental Biotechnology, KRIBB School of Biotechnology, Korea University of Science and Technology (UST), 217 Gajeong-ro, Yuseong-gu, Daejeon 34113, Republic of Korea.
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5
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Labban A, Palacio AS, García FC, Hadaidi G, Ansari MI, López-Urrutia Á, Alonso-Sáez L, Hong PY, Morán XAG. Temperature Responses of Heterotrophic Bacteria in Co-culture With a Red Sea Synechococcus Strain. Front Microbiol 2021; 12:612732. [PMID: 34040590 PMCID: PMC8141594 DOI: 10.3389/fmicb.2021.612732] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 03/29/2021] [Indexed: 11/29/2022] Open
Abstract
Interactions between autotrophic and heterotrophic bacteria are fundamental for marine biogeochemical cycling. How global warming will affect the dynamics of these essential microbial players is not fully understood. The aims of this study were to identify the major groups of heterotrophic bacteria present in a Synechococcus culture originally isolated from the Red Sea and assess their joint responses to experimental warming within the metabolic ecology framework. A co-culture of Synechococcus sp. RS9907 and their associated heterotrophic bacteria, after determining their taxonomic affiliation by 16S rRNA gene sequencing, was acclimated and maintained in the lab at different temperatures (24-34°C). The abundance and cellular properties of Synechococcus and the three dominant heterotrophic bacterial groups (pertaining to the genera Paracoccus, Marinobacter, and Muricauda) were monitored by flow cytometry. The activation energy of Synechococcus, which grew at 0.94-1.38 d-1, was very similar (0.34 ± 0.02 eV) to the value hypothesized by the metabolic theory of ecology (MTE) for autotrophs (0.32 eV), while the values of the three heterotrophic bacteria ranged from 0.16 to 1.15 eV and were negatively correlated with their corresponding specific growth rates (2.38-24.4 d-1). The corresponding carrying capacities did not always follow the inverse relationship with temperature predicted by MTE, nor did we observe a consistent response of bacterial cell size and temperature. Our results show that the responses to future ocean warming of autotrophic and heterotrophic bacteria in microbial consortia might not be well described by theoretical universal rules.
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Affiliation(s)
- Abbrar Labban
- Red Sea Research Center, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
- Water Desalination and Reuse Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Antonio S. Palacio
- AZTI, Marine Research, Basque Research and Technology Alliance (BRTA), Sukarrieta, Spain
| | - Francisca C. García
- Environment and Sustainability Institute, University of Exeter, Penryn, United Kingdom
| | - Ghaida Hadaidi
- Red Sea Research Center, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | - Mohd I. Ansari
- Red Sea Research Center, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | - Ángel López-Urrutia
- Centro Oceanográfico de Gijón/Xixón, Instituto Español de Oceanografía, Gijón, Spain
| | - Laura Alonso-Sáez
- AZTI, Marine Research, Basque Research and Technology Alliance (BRTA), Sukarrieta, Spain
| | - Pei-Ying Hong
- Water Desalination and Reuse Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Xosé Anxelu G. Morán
- Red Sea Research Center, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
- Centro Oceanográfico de Gijón/Xixón, Instituto Español de Oceanografía, Gijón, Spain
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6
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Sabbagh EI, Huete-Stauffer TM, Calleja MLL, Silva L, Viegas M, Morán XAG. Weekly variations of viruses and heterotrophic nanoflagellates and their potential impact on bacterioplankton in shallow waters of the central Red Sea. FEMS Microbiol Ecol 2020; 96:5800985. [PMID: 32149360 PMCID: PMC7104677 DOI: 10.1093/femsec/fiaa033] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 03/08/2020] [Indexed: 11/14/2022] Open
Abstract
Bacterioplankton play a pivotal role in marine ecosystems. However, their temporal dynamics and underlying control mechanisms are poorly understood in tropical regions such as the Red Sea. Here, we assessed the impact of bottom-up (resource availability) and top-down (viruses and heterotrophic nanoflagellates) controls on bacterioplankton abundances by weekly sampling a coastal central Red Sea site in 2017. We monitored microbial abundances by flow cytometry together with a set of environmental variables including temperature, salinity, dissolved organic and inorganic nutrients and chlorophyll a. We distinguished five groups of heterotrophic bacteria depending on their physiological properties relative nucleic acid content, membrane integrity and cell-specific respiratory activity, two groups of Synechococcus cyanobacteria and three groups of viruses. Viruses controlled heterotrophic bacteria for most of the year, as supported by a negative correlation between their respective abundances and a positive one between bacterial mortality rates and mean viral abundances. On the contrary, heterotrophic nanoflagellates abundance covaried with that of heterotrophic bacteria. Heterotrophic nanoflagellates showed preference for larger bacteria from both the high and low nucleic acid content groups. Our results demonstrate that top-down control is fundamental in keeping heterotrophic bacterioplankton abundances low (< 5 × 10 5 cells mL−1) in Red Sea coastal waters.
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Affiliation(s)
- Eman I Sabbagh
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Biological and Environmental Sciences and Engineering Division, Thuwal, Kingdom of Saudi Arabia
| | - Tamara M Huete-Stauffer
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Biological and Environmental Sciences and Engineering Division, Thuwal, Kingdom of Saudi Arabia
| | - Maria L L Calleja
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Biological and Environmental Sciences and Engineering Division, Thuwal, Kingdom of Saudi Arabia.,Max Planck Institute for Chemistry, Hahn-Meitner Weg 1, 55128 Mainz, Germany
| | - Luis Silva
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Biological and Environmental Sciences and Engineering Division, Thuwal, Kingdom of Saudi Arabia
| | - Miguel Viegas
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Biological and Environmental Sciences and Engineering Division, Thuwal, Kingdom of Saudi Arabia
| | - Xosé Anxelu G Morán
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Biological and Environmental Sciences and Engineering Division, Thuwal, Kingdom of Saudi Arabia
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7
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Ullah R, Yasir M, Bibi F, Abujamel TS, Hashem AM, Sohrab SS, Al-Ansari A, Al-Sofyani AA, Al-Ghamdi AK, Al-Sieni A, Azhar EI. Taxonomic diversity of antimicrobial-resistant bacteria and genes in the Red Sea coast. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 677:474-483. [PMID: 31063890 DOI: 10.1016/j.scitotenv.2019.04.283] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 03/26/2019] [Accepted: 04/18/2019] [Indexed: 06/09/2023]
Abstract
Despite development of a record number of recreational sites and industrial zones on the Red Sea coast in the last decade, antibiotic-resistant bacteria in this environment remain largely unexplored. In this study, 16S rDNA sequencing was used to identify bacteria isolated from 12 sediment samples collected from the Red Sea coastal, offshore, and mangroves sites. Quantitative PCR was used to estimate the quantity of antimicrobial resistance genes (ARGs) in genomic DNA in the samples. A total of 470 bacteria were isolated and classified into 137 distinct species, including 10 candidate novel species. Site-specific bacterial communities inhabiting the Red Sea were apparent. Relatively, more resistant isolates were recovered from the coast, and samples from offshore locations contained the most multidrug-resistant bacteria. Eighteen ARGs were detected in this study encoding resistance to aminoglycoside, beta-lactam, sulfonamide, macrolide, quinolone, and tetracycline antibiotics. The qnrS, aacC2, ermC, and blaTEM-1 genes were commonly found in coastal and offshore sites. Relatively higher abundance of ARGs, including aacC2 and aacC3, were found in the apparently anthropogenically contaminated (beach) samples from coast compared to other collected samples. In conclusion, a relative increase in antimicrobial-resistant isolates was found in sediment samples from the Red Sea, compared to other studies. Anthropogenic activities likely contribute to this increase in bacterial diversity and ARGs.
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Affiliation(s)
- Riaz Ullah
- Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia; Biochemistry Department, Faculty of Science, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Muhammad Yasir
- Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia; Medical Laboratory Technology Department, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia.
| | - Fehmida Bibi
- Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia; Medical Laboratory Technology Department, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Turki S Abujamel
- Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia; Medical Laboratory Technology Department, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Anwar M Hashem
- Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia; Department of Medical Microbiology and Parasitology, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Sayed Sartaj Sohrab
- Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia; Medical Laboratory Technology Department, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Ahmed Al-Ansari
- Department of Environmental Sciences, Faculty of Meteorology, Environment and Arid Land Agriculture, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Abdulmohsin A Al-Sofyani
- Marine Biology Department, Faculty of Marine Science, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Ahmed K Al-Ghamdi
- Medical Laboratory Technology Department, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Abdulbasit Al-Sieni
- Biochemistry Department, Faculty of Science, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Esam I Azhar
- Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia; Medical Laboratory Technology Department, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
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8
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Microbial diversity and biosignatures of amorphous silica deposits in orthoquartzite caves. Sci Rep 2018; 8:17569. [PMID: 30514906 PMCID: PMC6279750 DOI: 10.1038/s41598-018-35532-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Accepted: 10/30/2018] [Indexed: 11/08/2022] Open
Abstract
Chemical mobility of crystalline and amorphous SiO2 plays a fundamental role in several geochemical and biological processes, with silicate minerals being the most abundant components of the Earth's crust. Although the oldest evidences of life on Earth are fossilized in microcrystalline silica deposits, little is known about the functional role that bacteria can exert on silica mobility at non-thermal and neutral pH conditions. Here, a microbial influence on silica mobilization event occurring in the Earth's largest orthoquartzite cave is described. Transition from the pristine orthoquartzite to amorphous silica opaline precipitates in the form of stromatolite-like structures is documented through mineralogical, microscopic and geochemical analyses showing an increase of metals and other bioessential elements accompanied by permineralized bacterial cells and ultrastructures. Illumina sequencing of the 16S rRNA gene describes the bacterial diversity characterizing the consecutive amorphization steps to provide clues on the biogeochemical factors playing a role in the silica solubilization and precipitation processes. These results show that both quartz weathering and silica mobility are affected by chemotrophic bacterial communities, providing insights for the understanding of the silica cycle in the subsurface.
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9
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Ghosh A, Bhadury P. Investigating monsoon and post-monsoon variabilities of bacterioplankton communities in a mangrove ecosystem. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:5722-5739. [PMID: 29230649 DOI: 10.1007/s11356-017-0852-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Accepted: 11/27/2017] [Indexed: 06/07/2023]
Abstract
In mangrove environments, bacterioplankton communities constitute an important component of aquatic biota and play a major role in ecosystem processes. Variability of bacterioplankton communities from Sundarbans mangrove, located in the Indian subcontinent in South Asia and sits on the apex of Bay of Bengal, was investigated over monsoon and post-monsoon seasons. The study was undertaken in two stations in Sundarbans using 16S rRNA clone library and Illumina MiSeq approaches with focus on the functionally important members that participate in coastal biogeochemical cycling. Out of 544 sequenced clones, Proteobacteria dominated the study area (373 sequences) with persistence of two major classes, namely, Gammaproteobacteria and Alphaproteobacteria across both monsoon and post-monsoon seasons in both stations. Several sequences belonging to Sphingomonadales, Chromatiales, Alteromonadales, Oceanospirillales, and Bacteroidetes were encountered that are known to play important roles in coastal carbon cycling. Some sequences showed identity with published uncultured Planctomycetes and Chloroflexi highlighting their role in nitrogen cycling. The detection of two novel clades highlighted the existence of indigenous group of bacterioplankton that may play important roles in this ecosystem. The eubacterial V3-V4 region from environmental DNA extracted from the above two stations, followed by sequencing in Illumina MiSeq system, was also targeted in the study. A congruency between the clone library and Illumina approaches was observed. Strong variability in bacterioplankton community structure was encountered at a seasonal scale in link with precipitation. Drastic increase in sediment associated bacteria such as members of Firmicutes and Desulfovibrio was found in monsoon hinting possible resuspension of sediment-dwelling bacteria into the overlying water column. Principal component analysis (PCA) revealed dissolved ammonium and dissolved nitrate to account for maximum variation observed in the bacterioplankton community structure. Overall, the study showed that a strong interplay exists between environmental parameters and observed variability in bacterioplankton communities as a result of precipitation which can ultimately influence processes and rates linked to coastal biogeochemical cycles.
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Affiliation(s)
- Anwesha Ghosh
- Integrative Taxonomy and Microbial Ecology Research Group, Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, Nadia, West Bengal, 741246, India
| | - Punyasloke Bhadury
- Integrative Taxonomy and Microbial Ecology Research Group, Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, Nadia, West Bengal, 741246, India.
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10
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Ramees TP, Dhama K, Karthik K, Rathore RS, Kumar A, Saminathan M, Tiwari R, Malik YS, Singh RK. Arcobacter: an emerging food-borne zoonotic pathogen, its public health concerns and advances in diagnosis and control - a comprehensive review. Vet Q 2017; 37:136-161. [PMID: 28438095 DOI: 10.1080/01652176.2017.1323355] [Citation(s) in RCA: 93] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Arcobacter has emerged as an important food-borne zoonotic pathogen, causing sometimes serious infections in humans and animals. Newer species of Arcobacter are being incessantly emerging (presently 25 species have been identified) with novel information on the evolutionary mechanisms and genetic diversity among different Arcobacter species. These have been reported from chickens, domestic animals (cattle, pigs, sheep, horses, dogs), reptiles (lizards, snakes and chelonians), meat (poultry, pork, goat, lamb, beef, rabbit), vegetables and from humans in different countries. Arcobacters are implicated as causative agents of diarrhea, mastitis and abortion in animals, while causing bacteremia, endocarditis, peritonitis, gastroenteritis and diarrhea in humans. Three species including A. butzleri, A. cryaerophilus and A. skirrowii are predominantly associated with clinical conditions. Arcobacters are primarily transmitted through contaminated food and water sources. Identification of Arcobacter by biochemical tests is difficult and isolation remains the gold standard method. Current diagnostic advances have provided various molecular methods for efficient detection and differentiation of the Arcobacters at genus and species level. To overcome the emerging antibiotic resistance problem there is an essential need to explore the potential of novel and alternative therapies. Strengthening of the diagnostic aspects is also suggested as in most cases Arcobacters goes unnoticed and hence the exact epidemiological status remains uncertain. This review updates the current knowledge and many aspects of this important food-borne pathogen, namely etiology, evolution and emergence, genetic diversity, epidemiology, the disease in animals and humans, public health concerns, and advances in its diagnosis, prevention and control.
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Affiliation(s)
- Thadiyam Puram Ramees
- a Division of Veterinary Public Health , ICAR-Indian Veterinary Research Institute (IVRI) , Bareilly , India
| | - Kuldeep Dhama
- b Division of Pathology , ICAR-Indian Veterinary Research Institute (IVRI) , Bareilly , India
| | - Kumaragurubaran Karthik
- c Central University Laboratory , Tamil Nadu Veterinary and Animal Sciences University , Chennai , India
| | - Ramswaroop Singh Rathore
- a Division of Veterinary Public Health , ICAR-Indian Veterinary Research Institute (IVRI) , Bareilly , India
| | - Ashok Kumar
- a Division of Veterinary Public Health , ICAR-Indian Veterinary Research Institute (IVRI) , Bareilly , India
| | - Mani Saminathan
- b Division of Pathology , ICAR-Indian Veterinary Research Institute (IVRI) , Bareilly , India
| | - Ruchi Tiwari
- d Department of Veterinary Microbiology and Immunology, College of Veterinary Sciences , UP Pandit Deen Dayal Upadhayay Pashu Chikitsa Vigyan Vishwavidyalay Evum Go-Anusandhan Sansthan (DUVASU) , Mathura , India
| | - Yashpal Singh Malik
- e Division of Biological Standardization , ICAR-Indian Veterinary Research Institute (IVRI) , Bareilly , India
| | - Raj Kumar Singh
- f ICAR-Indian Veterinary Research Institute (IVRI) , Bareilly , India
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Microbial planktonic communities in the Red Sea: high levels of spatial and temporal variability shaped by nutrient availability and turbulence. Sci Rep 2017; 7:6611. [PMID: 28747798 PMCID: PMC5529573 DOI: 10.1038/s41598-017-06928-z] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Accepted: 06/28/2017] [Indexed: 12/20/2022] Open
Abstract
The semi-enclosed nature of the Red Sea (20.2°N-38.5°N) makes it a natural laboratory to study the influence of environmental gradients on microbial communities. This study investigates the composition and structure of microbial prokaryotes and eukaryotes using molecular methods, targeting ribosomal RNA genes across different regions and seasons. The interaction between spatial and temporal scales results in different scenarios of turbulence and nutrient conditions allowing for testing of ecological theory that categorizes the response of the plankton community to these variations. The prokaryotic reads are mainly comprised of Cyanobacteria and Proteobacteria (Alpha and Gamma), with eukaryotic reads dominated by Dinophyceae and Syndiniophyceae. Periodic increases in the proportion of Mamiellophyceae and Bacillariophyceae reads were associated with alterations in the physical oceanography leading to nutrient increases either through the influx of Gulf of Aden Intermediate Water (south in the fall) or through water column mixing processes (north in the spring). We observed that in general dissimilarity amongst microbial communities increased when nutrient concentrations were higher, whereas richness (observed OTUs) was higher in scenarios of higher turbulence. Maximum abundance models showed the differential responses of dominant taxa to temperature giving an indication how taxa will respond as waters become warmer and more oligotrophic.
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12
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Toh BEW, Bokhari O, Kutbi A, Haroon MF, Mantilla‐Calderon D, Zowawi H, Hong P. Varying occurrence of extended‐spectrum beta‐lactamase bacteria among three produce types. J Food Saf 2017. [DOI: 10.1111/jfs.12373] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Benjamin E. W. Toh
- Biological and Environmental Science & Engineering DivisionKing Abdullah University of Science and Technology, Water Desalination and Reuse CenterThuwal Saudi Arabia
| | - Osama Bokhari
- Biological and Environmental Science & Engineering DivisionKing Abdullah University of Science and Technology, Water Desalination and Reuse CenterThuwal Saudi Arabia
| | - Abdullah Kutbi
- Biological and Environmental Science & Engineering DivisionKing Abdullah University of Science and Technology, Water Desalination and Reuse CenterThuwal Saudi Arabia
| | - Mohamed Fauzi Haroon
- Biological and Environmental Science & Engineering DivisionKing Abdullah University of Science and Technology, Red Sea Research CenterThuwal Saudi Arabia
| | - David Mantilla‐Calderon
- Biological and Environmental Science & Engineering DivisionKing Abdullah University of Science and Technology, Water Desalination and Reuse CenterThuwal Saudi Arabia
| | - Hosam Zowawi
- UQ Centre for Clinical ResearchThe University of Queensland, Queensland, Royal Brisbane and Women's Hospital CampusBrisbane Australia
- King Saud bin Abdulaziz University for Health SciencesRiyadh Saudi Arabia
- World Health Organization Collaborating Centre for Infection Prevention and Control and Gulf Cooperation Council Center for Infection ControlRiyadh Saudi Arabia
| | - Pei‐Ying Hong
- Biological and Environmental Science & Engineering DivisionKing Abdullah University of Science and Technology, Water Desalination and Reuse CenterThuwal Saudi Arabia
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Scarascia G, Cheng H, Harb M, Hong PY. Application of hierarchical oligonucleotide primer extension (HOPE) to assess relative abundances of ammonia- and nitrite-oxidizing bacteria. BMC Microbiol 2017; 17:85. [PMID: 28376730 PMCID: PMC5381152 DOI: 10.1186/s12866-017-0998-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Accepted: 04/01/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Establishing an optimal proportion of nitrifying microbial populations, including ammonia-oxidizing bacteria (AOB), nitrite-oxidizing bacteria (NOB), complete nitrite oxidizers (comammox) and ammonia-oxidizing archaea (AOA), is important for ensuring the efficiency of nitrification in water treatment systems. Hierarchical oligonucleotide primer extension (HOPE), previously developed to rapidly quantify relative abundances of specific microbial groups of interest, was applied in this study to track the abundances of the important nitrifying bacterial populations. RESULTS The method was tested against biomass obtained from a laboratory-scale biofilm-based trickling reactor, and the findings were validated against those obtained by 16S rRNA gene-based amplicon sequencing. Our findings indicated a good correlation between the relative abundance of nitrifying bacterial populations obtained using both HOPE and amplicon sequencing. HOPE showed a significant increase in the relative abundance of AOB, specifically Nitrosomonas, with increasing ammonium content and shock loading (p < 0.001). In contrast, Nitrosospira remained stable in its relative abundance against the total community throughout the operational phases. There was a corresponding significant decrease in the relative abundance of NOB, specifically Nitrospira and those affiliated to comammox, during the shock loading. Based on the relative abundance of AOB and NOB (including commamox) obtained from HOPE, it was determined that the optimal ratio of AOB against NOB ranged from 0.2 to 2.5 during stable reactor performance. CONCLUSIONS Overall, the HOPE method was developed and validated against 16S rRNA gene-based amplicon sequencing for the purpose of performing simultaneous monitoring of relative abundance of nitrifying populations. Quantitative measurements of these nitrifying populations obtained via HOPE would be indicative of reactor performance and nitrification functionality.
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Affiliation(s)
- Giantommaso Scarascia
- Biological and Environmental Science & Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Water Desalination and Reuse Center (WDRC), Thuwal, 23955-6900, Saudi Arabia
| | - Hong Cheng
- Biological and Environmental Science & Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Water Desalination and Reuse Center (WDRC), Thuwal, 23955-6900, Saudi Arabia
| | - Moustapha Harb
- Biological and Environmental Science & Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Water Desalination and Reuse Center (WDRC), Thuwal, 23955-6900, Saudi Arabia
| | - Pei-Ying Hong
- Biological and Environmental Science & Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Water Desalination and Reuse Center (WDRC), Thuwal, 23955-6900, Saudi Arabia.
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14
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Roik A, Röthig T, Roder C, Ziegler M, Kremb SG, Voolstra CR. Year-Long Monitoring of Physico-Chemical and Biological Variables Provide a Comparative Baseline of Coral Reef Functioning in the Central Red Sea. PLoS One 2016; 11:e0163939. [PMID: 27828965 PMCID: PMC5102394 DOI: 10.1371/journal.pone.0163939] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Accepted: 09/16/2016] [Indexed: 11/26/2022] Open
Abstract
Coral reefs in the central Red Sea are sparsely studied and in situ data on physico-chemical and key biotic variables that provide an important comparative baseline are missing. To address this gap, we simultaneously monitored three reefs along a cross-shelf gradient for an entire year over four seasons, collecting data on currents, temperature, salinity, dissolved oxygen (DO), chlorophyll-a, turbidity, inorganic nutrients, sedimentation, bacterial communities of reef water, and bacterial and algal composition of epilithic biofilms. Summer temperature (29–33°C) and salinity (39 PSU) exceeded average global maxima for coral reefs, whereas DO concentration was low (2–4 mg L-1). While temperature and salinity differences were most pronounced between seasons, DO, chlorophyll-a, turbidity, and sedimentation varied most between reefs. Similarly, biotic communities were highly dynamic between reefs and seasons. Differences in bacterial biofilms were driven by four abundant families: Rhodobacteraceae, Flavobacteriaceae, Flammeovirgaceae, and Pseudanabaenaceae. In algal biofilms, green crusts, brown crusts, and crustose coralline algae were most abundant and accounted for most of the variability of the communities. Higher bacterial diversity of biofilms coincided with increased algal cover during spring and summer. By employing multivariate matching, we identified temperature, salinity, DO, and chlorophyll-a as the main contributing physico-chemical drivers of biotic community structures. These parameters are forecast to change most with the progression of ocean warming and increased nutrient input, which suggests an effect on the recruitment of Red Sea benthic communities as a result of climate change and anthropogenic influence. In conclusion, our study provides insight into coral reef functioning in the Red Sea and a comparative baseline to support coral reef studies in the region.
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Affiliation(s)
- Anna Roik
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology, Thuwal, 23955–6900, Saudi Arabia
| | - Till Röthig
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology, Thuwal, 23955–6900, Saudi Arabia
| | - Cornelia Roder
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology, Thuwal, 23955–6900, Saudi Arabia
| | - Maren Ziegler
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology, Thuwal, 23955–6900, Saudi Arabia
| | - Stephan G. Kremb
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology, Thuwal, 23955–6900, Saudi Arabia
| | - Christian R. Voolstra
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology, Thuwal, 23955–6900, Saudi Arabia
- * E-mail:
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15
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Isolation and Characterization of NDM-Positive Escherichia coli from Municipal Wastewater in Jeddah, Saudi Arabia. Antimicrob Agents Chemother 2016; 60:5223-31. [PMID: 27324770 PMCID: PMC4997845 DOI: 10.1128/aac.00236-16] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 06/09/2016] [Indexed: 11/22/2022] Open
Abstract
The emergence of resistance to last-resort antibiotics is a public health concern of global scale. Besides direct person-to-person propagation, environmental pathways might contribute to the dissemination of antibiotic-resistant bacteria and antibiotic resistance genes (ARGs). Here, we describe the incidence of blaNDM-1, a gene conferring resistance to carbapenems, in the wastewater of the city of Jeddah, Saudi Arabia, over a 1-year period. blaNDM-1 was detected at concentrations ranging from 104 to 105 copies/m3 of untreated wastewater during the entire monitoring period. These results indicate the ubiquity and high incidence of blaNDM-1 in the local wastewater. To track the bacteria carrying blaNDM-1, we isolated Escherichia coli PI7, a strain of sequence type 101 (ST101), from wastewater around the Hajj event in October 2013. Genome sequencing of this strain revealed an extensive repertoire of ARGs as well as virulence and invasive traits. These traits were further confirmed by antibiotic resistance profiling and in vitro cell internalization in HeLa cell cultures. Given that this strain remains viable even after a certain duration in the sewerage, and that Jeddah lacks a robust sanitary infrastructure to fully capture all generated sewage, the presence of this bacterium in the untreated wastewater represents a potential hazard to the local public health. To the best of our knowledge, this is the first report of a blaNDM-1-positive E. coli strain isolated from a nonnosocomial environment in Saudi Arabia and may set a priority concern for the need to establish improved surveillance for carbapenem-resistant E. coli in the country and nearby regions.
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Pearman JK, Kürten S, Sarma YVB, Jones BH, Carvalho S. Biodiversity patterns of plankton assemblages at the extremes of the Red Sea. FEMS Microbiol Ecol 2016; 92:fiw002. [PMID: 26738552 DOI: 10.1093/femsec/fiw002] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/29/2015] [Indexed: 11/13/2022] Open
Abstract
The diversity of microbial plankton has received limited attention in the main basin of the Red Sea. This study investigates changes in the community composition and structure of prokaryotes and eukaryotes at the extremes of the Red Sea along cross-shelf gradients and between the surface and deep chlorophyll maximum. Using molecular methods to target both the 16S and 18S rRNA genes, it was observed that the dominant prokaryotic classes were Acidimicrobiia, Alphaproteobacteria and Cyanobacteria, regardless of the region and depth. The eukaryotes Syndiniophyceae and Dinophyceae between them dominated in the north, with Bacillariophyceae and Mamiellophyceae more prominent in the southern region. Significant differences were observed for prokaryotes and eukaryotes for region, depth and distance from shore. Similarly, it was noticed that communities became less similar with increasing distance from the shore. Canonical correspondence analysis at the class level showed that Mamiellophyceae and Bacillariophyceae correlated with increased nutrients and chlorophyll a found in the southern region, which is influenced by the input of Gulf of Aden Intermediate Water.
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Affiliation(s)
- J K Pearman
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center (RSRC), Biological and Environmental Sciences & Engineering Division (BESE), Thuwal, 23955-6900, Saudi Arabia
| | - S Kürten
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center (RSRC), Biological and Environmental Sciences & Engineering Division (BESE), Thuwal, 23955-6900, Saudi Arabia
| | - Y V B Sarma
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center (RSRC), Biological and Environmental Sciences & Engineering Division (BESE), Thuwal, 23955-6900, Saudi Arabia
| | - B H Jones
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center (RSRC), Biological and Environmental Sciences & Engineering Division (BESE), Thuwal, 23955-6900, Saudi Arabia
| | - S Carvalho
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center (RSRC), Biological and Environmental Sciences & Engineering Division (BESE), Thuwal, 23955-6900, Saudi Arabia
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Alsalah D, Al-Jassim N, Timraz K, Hong PY. Assessing the Groundwater Quality at a Saudi Arabian Agricultural Site and the Occurrence of Opportunistic Pathogens on Irrigated Food Produce. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2015; 12:12391-411. [PMID: 26445052 PMCID: PMC4626975 DOI: 10.3390/ijerph121012391] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Revised: 09/15/2015] [Accepted: 09/22/2015] [Indexed: 11/16/2022]
Abstract
This study examines the groundwater quality in wells situated near agricultural fields in Saudi Arabia. Fruits (e.g., tomato and green pepper) irrigated with groundwater were also assessed for the occurrence of opportunistic pathogens to determine if food safety was compromised by the groundwater. The amount of total nitrogen in most of the groundwater samples exceeded the 15 mg/L permissible limit for agricultural irrigation. Fecal coliforms in densities > 12 MPN/100 mL were detected in three of the groundwater wells that were in close proximity to a chicken farm. These findings, coupled with qPCR-based fecal source tracking, show that groundwater in wells D and E, which were nearest to the chicken farm, had compromised quality. Anthropogenic contamination resulted in a shift in the predominant bacterial phyla within the groundwater microbial communities. For example, there was an elevated presence of Proteobacteria and Cyanobacteria in wells D and E but a lower overall microbial richness in the groundwater perturbed by anthropogenic contamination. In the remaining wells, the genus Acinetobacter was detected at high relative abundance ranging from 1.5% to 48% of the total groundwater microbial community. However, culture-based analysis did not recover any antibiotic-resistant bacteria or opportunistic pathogens from these groundwater samples. In contrast, opportunistic pathogenic Enterococcus faecalis and Pseudomonas aeruginosa were isolated from the fruits irrigated with the groundwater from wells B and F. Although the groundwater was compromised, quantitative microbial risk assessment suggests that the annual risk incurred from accidental consumption of E. faecalis on these fruits was within the acceptable limit of 10−4. However, the annual risk arising from P. aeruginosa was 9.55 × 10−4, slightly above the acceptable limit. Our findings highlight that the groundwater quality at this agricultural site in western Saudi Arabia is not pristine and that better agricultural management practices are needed alongside groundwater treatment strategies to improve food safety.
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Affiliation(s)
- Dhafer Alsalah
- Water Desalination and Reuse Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia.
| | - Nada Al-Jassim
- Water Desalination and Reuse Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia.
| | - Kenda Timraz
- Water Desalination and Reuse Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia.
| | - Pei-Ying Hong
- Water Desalination and Reuse Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia.
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