A5065927577- Microbial Community Ecology and Physiology
- Marine and coastal ecosystems
- Wastewater Treatment and Nitrogen Removal
- Genomics and Phylogenetic Studies
- Protist diversity and phylogeny
- Biofuel production and bioconversion
- Marine Biology and Ecology Research
- Methane Hydrates and Related Phenomena
- Coastal wetland ecosystem dynamics
- Anaerobic Digestion and Biogas Production
- Soil and Water Nutrient Dynamics
- Groundwater and Isotope Geochemistry
- Parasitic Infections and Diagnostics
- Mycobacterium research and diagnosis
- Bacteriophages and microbial interactions
- Isotope Analysis in Ecology
- Plant Pathogens and Fungal Diseases
- Soil and Unsaturated Flow
- Marine and coastal plant biology
- Microbial Metabolic Engineering and Bioproduction
- Tuberculosis Research and Epidemiology
- Fecal contamination and water quality
- Groundwater flow and contamination studies
- Evolution and Genetic Dynamics
- Travel-related health issues
University of California, Santa Barbara
2016-2025
University of South Carolina
2021-2024
University of South Carolina Sumter
2023-2024
Princeton University
2013-2021
Changsha Central Hospital
2011-2019
Institute of Deep-Sea Science and Engineering
2018
Chinese Academy of Sciences
2018
Connecticut College
2013
University College Dublin
2008-2011
Institute of Soil Science
2011
Abstract The herbivore digestive tract is home to a complex community of anaerobic microbes that work together break down lignocellulose. These microbiota are an untapped resource strains, pathways and enzymes could be applied convert plant waste into sugar substrates for green biotechnology. We carried out more than 400 parallel enrichment experiments from goat faeces determine how substrate antibiotic selection influence membership, activity, stability chemical productivity gut...
Cycles of wetting and drying (WD) occur naturally in soils affect the pore structure through altered hydraulic stresses. Two organic‐rich soils, a Eutric Histosol Histic Gleysol, two inorganic Calcic Gleysol Dystric ranging texture microstructure, were investigated. Undisturbed soil samples predried to either −100 kPa water potential by using ceramic plate or 30°C an oven then resaturated for one three WD cycles. In addition, different combinations defined intensity, frequency, sequence...
Abstract Nitrification plays a key role in the marine nitrogen (N) cycle, including oceanic oxygen minimum zones (OMZs), which are hot spots for denitrification and anaerobic ammonia oxidation (anammox). Recent evidence suggests that nitrification links source (remineralized organic matter) sink (denitrification anammox) of fixed N directly steep oxycline OMZs. We performed shipboard incubations with 15 tracers to characterize depth distribution Eastern Tropical North Pacific (ETNP)....
Abstract Nitrification, the oxidation of ammonium ( ) to nitrite and nitrate ), is a component nitrogen (N) cycle internal fixed N pool. In oxygen minimum zones (OMZs), which are hotspots for oceanic loss, nitrification plays key role because it directly supplies substrates denitrification anaerobic ammonia (anammox), may compete with these same processes. However, control substrate concentrations on not well understood. We performed onboard incubations 15 N‐labeled measure rates in eastern...
Abstract Growing interest in understanding the relevance of marine fungi to food webs, biogeochemical cycling, and biological patterns necessitates establishing a context for interpreting future findings. To help establish this context, we summarize diversity cultured observed planktonic from across world. While exploring diversity, discovered that only half known fungal species have publicly available DNA locus, which hypothesize will likely hinder accurate high-throughput sequencing...
Abstract Changes in the sequence of an organism’s genome, i.e., mutations, are raw material evolution. The frequency and location mutations can be constrained by specific molecular mechanisms, such as diversity-generating retroelements (DGRs). DGRs have been characterized from cultivated bacteria bacteriophages, perform error-prone reverse transcription leading to being introduced target genes. DGR loci were also identified several metagenomes, but ecological roles evolutionary drivers these...
Abstract Nitrification, the oxidation of ammonium to nitrite and then nitrate, is often discounted as a source nitrate in euphotic zone waters due photoinhibition nitrifying microorganisms and/or competition for with phytoplankton. However, there have also been counterarguments that nitrification represents significant “regenerated” phytoplankton, augmenting “new” supplied via physical processes. If an appreciable zone, assumption balance between uptake organic matter export will...
Fungi in terrestrial environments are known to play a key role carbon and nitrogen biogeochemistry exhibit high diversity. In contrast, the diversity function of fungi ocean has remained underexplored largely neglected. eastern tropical North Pacific oxygen minimum zone, we examined fungal by sequencing internal transcribed spacer region 2 (ITS2) mining metagenome dataset collected from same region. Additionally, coupled 15N-tracer experiments with selective inhibition method determine...
Abstract Anaerobic gut fungi effectively degrade lignocellulose in the guts of large herbivores, but there remains a limited number isolated, publicly available, and sequenced strains that impede our understanding role anaerobic within microbial communities. We isolated characterized new fungal isolate, Neocallimastix cameroonii var. constans, providing transcriptomic genomic its ability to diverse carbohydrates. This strain was stably cultivated for multiple years vitro among members an...
Ammonia-oxidizing archaea (AOA) have been reported at high abundance in much of the global ocean, even environments, such as pelagic oxygen minimum zones (OMZs), where conditions seem unlikely to support aerobic ammonium oxidation. Due lack information on any potential alternative metabolism AOA, AOA community composition might be expected differ between oxic and anoxic environments. This hypothesis was tested by evaluating using a functional gene microarray that targets ammonia...
The metabolism of archaeal methanogens drives methane release into the environment and is critical to understanding global carbon cycling. Methanogenesis operates at a very low reducing potential compared other forms respiration therefore many anaerobic environments. Harnessing or altering methanogen has mitigate warming even be utilized for energy applications.Here, we report draft genome sequences isolated Methanobacterium bryantii, Methanosarcina spelaei, Methanosphaera cuniculi,...
Persistent organic pollutants (PCBs and PBDEs) were analysed in sediment core samples (0-2 cm) from the southern Mariana Trench at water depths of 7000-11000 m. ∑PCBs concentrations ranged 931 to 4195 pg/g, far higher than those recorded before marine sediments shallower depths.Toxic Equivalence (TEQ) dl-PCBs 0.650 -14.9 which is most surficial <500-2500 m ocean depth, recovered semi-industrial industrial areas.However, ∑ 8 PBDEs values (averaging ~136 pg/g) lower shelf areas past...
Abstract Salt marshes provide numerous valuable ecological services. In particular, nitrogen (N) removal in salt marsh sediments alleviates N loading to the coastal ocean. reduces threat of eutrophication caused by increased inputs from anthropogenic sources. It is unclear, however, whether chronic nutrient overenrichment alters capacity remove N. To assess effect enrichment on cycling sediments, we examined important cycle pathways experimental fertilization plots a New England marsh. We...
Marine macroalgae produce abundant and diverse polysaccharides, which contribute substantially to the organic matter exported deep ocean. Microbial degradation of these polysaccharides plays an important role in turnover macroalgal biomass. Various members
Since the discovery of ammonia-oxidizing archaea (AOA), new questions have arisen about population and community dynamics potential interactions between AOA Bacteria (AOB). We investigated effects long-term fertilization on AOB in Great Sippewissett Marsh, Falmouth, MA, USA to address some these questions. Sediment samples were collected from low high marsh habitats July 2009 replicate plots that received (LF), (HF), extra (XF) levels a mixed NPK fertilizer biweekly during growing season...
Abstract. The Santa Barbara Basin naturally experiences transient deoxygenation due to its unique geological setting in the southern California Borderland and seasonal changes ocean currents. Long-term measurements of basin showed that anoxic events subsequent nitrate exhaustion bottom waters have been occurring more frequently lasting longer over past decade. One characteristic is development extensive mats benthic nitrate-reducing sulfur-oxidizing bacteria, which are found at...
Abstract. As a key biogeochemical pathway in the marine nitrogen cycle, nitrification (ammonia oxidation and nitrite oxidation) converts most reduced form of – ammonium–ammonia (NH4+–NH3) into oxidized species (NO2-) nitrate (NO3-). In ocean, these processes are mainly performed by ammonia-oxidizing archaea (AOA) bacteria (AOB) nitrite-oxidizing (NOB). By transforming speciation providing substrates for removal, affects microbial community structure; productivity (including chemoautotrophic...
AME Aquatic Microbial Ecology Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout JournalEditorsSpecials 70:245-259 (2013) - DOI: https://doi.org/10.3354/ame01654 FEATURE ARTICLE Community composition of bacteria involved in fixed nitrogen loss water column two major oxygen minimum zones ocean Amal Jayakumar*, Xuefeng Peng, Bess B. Ward Department Geosciences, Princeton University, Princeton, New Jersey 08544, USA *Email:...
Salt marshes provide many key ecosystem services that have tremendous ecological and economic value. One critical service is the removal of fixed nitrogen from coastal waters, which limits negative effects eutrophication resulting increased nutrient supply. Nutrient enrichment salt marsh sediments results in higher rates cycling and, commonly, a concurrent increase flux nitrous oxide, an important greenhouse gas. Little known, however, regarding controls on microbial communities contribute...
Airborne microbial communities directly impact the health of humans, animals, plants, and receiving ecosystems. While airborne bacterial fungal have been studied by both cultivation-based methods metabarcoding surveys targeting specific molecular markers, fewer studies used shotgun metagenomics to study mycobiome. We analyzed diversity relative abundance fungi in nine metagenomes collected on clear days ("background") during dust storms Eastern Mediterranean. The negative correlation between...
Nitrous oxide (N 2 O) is important to Earth's climate because it a strong absorber of radiation and an ozone depletion agent. Increasing anthropogenic nitrogen input into the marine environment, especially coastal waters, has led increasing N O emissions. Identifying compounds that serve as substrates for production in waters reveals pathways helps us understand their control by environmental factors. In this study, sediments were collected from long-term fertilization site Great...