ORCID Profile
0000-0003-0911-5317
Current Organisation
City University of Hong Kong
Does something not look right? The information on this page has been harvested from data sources that may not be up to date. We continue to work with information providers to improve coverage and quality. To report an issue, use the Feedback Form.
Publisher: Frontiers Media SA
Date: 24-05-2016
Publisher: Elsevier BV
Date: 12-2015
DOI: 10.1016/J.CHEMOSPHERE.2015.07.054
Abstract: Understanding the role of heterotrophic-methanotrophic (H-Meth) communities is important for improvement of methane (CH4) oxidation capacities (MOC) particularly in conjunction with bio-product development in industrial bio-filters. Initially, a H-Meth consortium was established and enriched from marine sediments and characterized by next generation sequencing of the 16s rDNA gene. The enriched consortium was subjected to 10-50% CH4 (i.e., 0.20-1.6 CH4/O2 ratios) to study the effects on MOCs, biomass growth, fatty acid profiles and biopolymer (e.g. polyhydroxybutyrate PHB) content. Methylocystis, Methylophaga and Pseudoxanthomonas dominated the H-Meth consortium. Culture enrichment of the H-Meth consortium resulted in 15-20-folds higher MOC compared to seed sediments. Increasing CH4 concentration (and decreased O2 levels) yielded higher MOCs, but did not improve total fatty acid contents. PHB contents varied between 2.5% and 8.5% independently of CH4/O2 ratios. The results suggest that H-Meth consortia could potentially be used in industrial bio-filters for production of biopolymer/biofuel precursors from CH4.
Publisher: American Society for Microbiology
Date: 31-08-2021
DOI: 10.1128/MSYSTEMS.00510-21
Abstract: Despite the clinical importance of urinary diseases in cats, the presence of resident urine microbes has not been demonstrated in cats, and the role of these microbes as a community in urinary health remains unknown. Here, we have shown that cats with and without urinary tract disease harbor unique microbial communities in their urine.
Publisher: American Society for Microbiology
Date: 15-01-2015
DOI: 10.1128/AEM.02566-14
Abstract: Methanogenic archaea play a key role in biogas-producing anaerobic digestion and yet remain poorly taxonomically characterized. This is in part due to the limitations of low-throughput Sanger sequencing of a single (16S rRNA) gene, which in the past may have unders led methanogen ersity. In this study, archaeal communities from three sludge digesters in Hong Kong and one wastewater digester in China were examined using high-throughput pyrosequencing of the methyl coenzyme M reductase ( mcrA ) and 16S rRNA genes. Methanobacteriales , Methanomicrobiales , and Methanosarcinales were detected in each digester, indicating that both hydrogenotrophic and acetoclastic methanogenesis was occurring. Two sludge digesters had similar community structures, likely due to their similar design and feedstock. Taxonomic classification of the mcrA genes suggested that these digesters were dominated by acetoclastic methanogens, particularly Methanosarcinales , while the other digesters were dominated by hydrogenotrophic Methanomicrobiales . The proposed euryarchaeotal order Methanomassiliicoccales and the uncultured WSA2 group were detected with the 16S rRNA gene, and potential mcrA genes for these groups were identified. 16S rRNA gene sequencing also recovered several crenarchaeotal groups potentially involved in the initial anaerobic digestion processes. Overall, the two genes produced different taxonomic profiles for the digesters, while greater methanogen richness was detected using the mcrA gene, supporting the use of this functional gene as a complement to the 16S rRNA gene to better assess methanogen ersity. A significant positive correlation was detected between methane production and the abundance of mcrA transcripts in digesters treating sludge and wastewater s les, supporting the mcrA gene as a biomarker for methane yield.
Publisher: Springer Science and Business Media LLC
Date: 06-11-2015
DOI: 10.1038/SREP15204
Abstract: Genomes of two trichloroethene (TCE)-respiring Dehalococcoides ( Dhc ) mccartyi , strains MB and 11a, were sequenced to identify reductive dehalogenases (RDase) responsible for oraganohalide respiration. Transcription analyses were conducted to verify the roles of RDase subunit A genes ( rdhA ) in chloroethene respiration. Some interesting features of the strain MB draft genome include a large genome size, two CRISPR- cas type I systems and 38 rdhA genes. Strain 11a has a stream-lined genome with 11 rdhA genes, of which nine are distinct. Quantitative real-time PCR transcription analysis of RDase gene transcripts showed that a single RDase gene, designated mbrA , was up-regulated upon exposure to TCE and no other RDase genes were considerably expressed in strain MB. A single RDase gene, designated vcrA , was up-regulated upon exposure to TCE and expressed at a steady level until all chloroethenes were completely dechlorinated to ethene at 147 h in strain 11a. Overall, this study reports the genomes of two distinct Dhc strains both contain numerous uncharacterized RDase genes, but in each strain only one such gene was expressed highly during organohalide respiration.
Location: United States of America
No related grants have been discovered for Patrick K. H. Lee.