A5020534066- Enzyme Structure and Function
- Genomics and Phylogenetic Studies
- Anaerobic Digestion and Biogas Production
- Microbial Community Ecology and Physiology
- Metalloenzymes and iron-sulfur proteins
- Methane Hydrates and Related Phenomena
- Biotin and Related Studies
- RNA and protein synthesis mechanisms
- Amino Acid Enzymes and Metabolism
- Microbial metabolism and enzyme function
- Wastewater Treatment and Nitrogen Removal
- Antibiotic Resistance in Bacteria
- Folate and B Vitamins Research
- Microbial bioremediation and biosurfactants
- Redox biology and oxidative stress
- Biochemical and Molecular Research
- Computational Drug Discovery Methods
- Algal biology and biofuel production
- Microbial Metabolic Engineering and Bioproduction
- Plant and fungal interactions
- Biofuel production and bioconversion
- Alzheimer's disease research and treatments
- Polyamine Metabolism and Applications
- Protein Structure and Dynamics
- Bacterial Genetics and Biotechnology
Virginia Tech
2015-2024
Biocom
2016-2021
Carilion Clinic
2017
Oregon State University
2014
Valero Energy (United States)
2012
Confederated Tribes of Warm Springs
2012
Scientific Forming Technologies Corporation (United States)
2012
BP (Germany)
2012
University of Illinois Urbana-Champaign
1998-2005
University of Iowa
1989-1995
Methanogenesis, the biological production of methane, plays a pivotal role in global carbon cycle and contributes significantly to warming. The majority methane nature is derived from acetate. Here we report complete genome sequence an acetate-utilizing methanogen, Methanosarcina acetivorans C2A. Methanosarcineae are most metabolically diverse methanogens, thrive broad range environments, unique among Archaea forming complex multicellular structures. This diversity reflected M. . At...
Background Methanomicrobiales is the least studied order of methanogens. While these organisms appear to be more closely related Methanosarcinales in ribosomal-based phylogenetic analyses, they are metabolically similar Class I Methodology/Principal Findings In improve our understanding this lineage, we have completely sequenced genomes two members order, Methanocorpusculum labreanum Z and Methanoculleus marisnigri JR1, compared them with genome a third, Methanospirillum hungatei JF-1....
Twelve vaginal samples were collected from separate patients, processed anaerobically, and added to methanogenic enrichment medium. Methanogenic activity was detected in two samples, both of which patients with bacterial vaginosis. None the healthy yielded positive methanogen cultures. One sample a patient vaginosis did not show any detectable activity. Two isolates obtained one methanogen-positive identified as Methanobrevibacter smithii on basis morphological, cultural, immunological features.
Technological advancements including an open-cylindrical Penning trap with capacitively coupled ICR cell, selective ion accumulation a resolving quadrupole, and voltage gradient used during extraction from octopole trap, have individually improved dynamic range sensitivity in Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR MS). Documented here is new instrument utilizing these technologies toward the robust detection fragmentation of biomolecules >10 kDa. Up to 55-fold...
In mycobacteria, F(420), a deazaflavin derivative, acts as hydride transfer coenzyme for an F(420)-specific glucose-6-phosphate dehydrogenase (Fgd). Physiologically relevant reactions in the mycobacteria that use Fgd-generated reduced F(420) (F(420)H(2)) are unknown. this work, F(420)H(2) was found to be oxidized by NO only presence of oxygen. Further analysis demonstrated NO(2), produced from and O(2), oxidant. UV-visible spectroscopic NO-sensor-based analyses proved NO(2) NO. This reaction...
To the mounting evidence of nonribosomal functions for ribosomal proteins, we now add L7Ae as a subunit archaeal RNase P, ribonucleoprotein (RNP) that catalyzes 5'-maturation precursor tRNAs (pre-tRNAs). We first demonstrate coelutes with partially purified Methanococcus maripaludis (Mma) P activity. After establishing in vitro reconstitution single RNA four previously known protein subunits (POP5, RPP21, RPP29, and RPP30), show addition to this complex increases optimal reaction temperature...
The methanarchaeon, Methanococcus jannaschii, a hyperthermophilic, autotrophic, and strictly hydrogenotrophic inhabitant of submarine hydrothermal vents, was cultivated in reactor at two hydrogen partial pressure (p(H(2))) values, 178 kPa (high) 650 Pa (ultralow), the cells were subjected to comparative proteome analysis. From these studies, it discovered that, when p(H(2)) high cell density low (a combination representing hydrogen-excess condition), possessed very or undetectable levels...
Methanocaldococcus jannaschii is a hypertheromphilic, strictly hydrogenotrophic, methanogenic archaeon of ancient lineage isolated from deep-sea hydrothermal vent. It requires sulfide for growth. Sulfite inhibitory to the methanogens. Yet, we observed that M. grows and produces methane with sulfite as sole sulfur source. We found in this organism induces novel, highly active, coenzyme F420-dependent reductase (Fsr) cell extract specific activity 0.57 μmol reduced min-1 mg-1 protein. The...
The regulation of intracellular levels reactive oxygen species (ROS) is critical for developmental differentiation and virulence many pathogenic fungi. In this report we demonstrate that a novel transmembrane protein, TmpL, necessary ROS tolerance to external ROS, required infection plants by the necrotroph Alternaria brassicicola mammals human pathogen Aspergillus fumigatus. both fungi, tmpL encodes predicted hybrid membrane protein containing an AMP-binding domain, six putative domains,...
Sulfate is the predominant electron acceptor for anaerobic oxidation of methane (AOM) in marine sediments. This process carried out by a syntrophic consortium methanotrophic archaea (ANME) and sulfate reducing bacteria (SRB) through an energy conservation mechanism that still poorly understood. It was previously hypothesized ANME alone could couple to dissimilatory reduction, but genetic biochemical basis this proposal has not been identified. Using comparative genomic phylogenetic analyses,...
Significance This study extends thioredoxin (Trx)-based oxidative redox regulation to the archaea, third domain of life. Our suggests that Trx is nearly ubiquitous in anaerobic methanogens, enabling them recover from stress and synchronize cellular processes, including methane biogenesis, with availability reductants. As a valuable fuel, an end product biodegradation potent greenhouse gas, may now be considered critical participant global carbon cycle, climate change, bioenergy production....
As one of the most abundant materials in nature, lignin has been used widely co-generation operations and for fine chemicals bio-fuels production. These uses, although important, are relatively low value. Lignin contains many aromatic compounds with useful structures, it is potentially more profitable to produce high-value from low-molecular weight fraction while using high-molecular fuel or other applications. A transgenic P. putida bacterial strain PDHV85 was developed capability convert...
Summary A mutation in the mch gene, encoding enzyme 5,10‐methenyl tetrahydromethanopterin (H 4 MPT) cyclohydrolase, was constructed vitro and recombined onto chromosome of methanogenic archaeon Methanosarcina barkeri . The resulting mutant does not grow media using H 2 /CO , methanol, or acetate as carbon energy sources, but with methanol/H demonstrating its ability to utilize a source electrons for reduction methyl groups. Cell suspension experiments showed that methanogenesis from methanol...
ABSTRACT We report the complete genome of Thermofilum pendens , a deeply branching, hyperthermophilic member order Thermoproteales in archaeal kingdom Crenarchaeota. T. is sulfur-dependent, anaerobic heterotroph isolated from solfatara Iceland. It an extracellular commensal, requiring extract Thermoproteus tenax for growth, and sequence reveals that biosynthetic pathways purines, most amino acids, cofactors are absent. In fact, has fewer enzymes than obligate intracellular parasites,...
Hydrogenotrophic methanogenesis and dissimilatory sulfate reduction, two of the oldest energy conserving respiratory systems on Earth, apparently could not have evolved in same host, as sulfite, an intermediate inhibits methanogenesis. However, certain methanogenic archaea metabolize sulfite employing a deazaflavin cofactor (F420)-dependent reductase (Fsr) where N- C-terminal halves (Fsr-N Fsr-C) are homologs F420H2 dehydrogenase (Dsr), respectively. From genome analysis we found that Fsr...
The ability of Mycobacterium tuberculosis to manipulate and evade human immune system is in part due its extraordinarily complex cell wall. One the key components this wall a family lipids called mycolic acids. Oxygenation acids generating methoxy- ketomycolic enhances pathogenic attributes M. tuberculosis. Thus, respective enzymes are interest research on mycobacteria. generation proceeds through intermediary formation hydroxymycolic While methyl transferase that generates methoxymycolic...
Phylogenetically deeply rooted methanogens belonging to the genus of Methanocaldococcus living in deep-sea hydrothermal vents derive energy exclusively from hydrogenotrophic methanogenesis, one oldest respiratory metabolisms on Earth. These hyperthermophilic, autotrophic archaea synthesize their biomolecules inorganic substrates and perform high temperature biocatalysis producing methane, a valuable fuel potent greenhouse gas. The information processing stress response systems are highly...
ABSTRACT For the hyperthermophilic and barophilic methanarchaeon Methanococcus jannaschii , we have developed a medium protocols for reactor-scale cultivation that improved final cell yield per liter from ∼0.5 to ∼7.5 g of packed wet cells (∼1.8 dry mass) under autotrophic growth conditions ∼8.5 (∼2 with yeast extract (2 −1 ) tryptone as supplements. in sealed bottle it was necessary add Se medium, level 2 μM added gave highest yield. In reactor M. grew without medium; is plausible received...
We discovered thatMethanobacterium thermoautotrophicum strain ΔH possessed pyruvate carboxylase (PYC), and this biotin prototroph required exogenously supplied to exhibit detectable amounts of PYC activity. The enzyme was highly labile stabilized by 10% inositol in buffers an extent that allowed purification homogeneity characterization. purified absolutely dependent on ATP, Mg2+ (or Mn2+ or Co2+), pyruvate, bicarbonate for activity; phosphoenolpyruvate could not replace acetyl-CoA required....
The N 5 ,N 10 -methylenetetrahydromethanopterin dehydrogenase from Methanobacterium thermoautotrophicum strain Marburg has been purified with reasonable yield and much higher specific activity than previously reported. For the first time it shown that both -methenyltetrahydromethanopterin cyclohydrolase activities were stable under air could be using aerobic operations. was in phosphate buffer or without glycerol ammonium sulfate anaerobic conditions. However, presence of either...
Coenzyme F(420)-dependent sulfite reductase (Fsr) of Methanocaldococcus jannaschii, a sulfite-tolerant methanogen, was expressed with activity in Methanococcus maripaludis, sulfite-sensitive methanogen. The recombinant organism reduced to sulfide and grew as the sole sulfur source, indicating that Fsr is detoxification assimilation enzyme for methanogens M. maripaludis synthesizes siroheme.