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Li X, Zeng C, Lu Y, Liu G, Luo H, Zhang R. Development of methanogens within cathodic biofilm in the single-chamber microbial electrolysis cell. BIORESOURCE TECHNOLOGY 2019; 274:403-409. [PMID: 30551043 DOI: 10.1016/j.biortech.2018.12.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 11/28/2018] [Accepted: 12/01/2018] [Indexed: 06/09/2023]
Abstract
The aim of this study was to investigate the development of cathodic biofilm and its effect on methane production in a single-chamber microbial electrolysis cell (MEC). The MEC with 1 g/L acetate was successfully operated within 31 cycles (∼2400 h). The maximum methane production rate and average current capture efficiency in the MEC reached 93 L/m3·d and 82%, respectively. Distinct stratification of Methanobacteriaceae within cathodic biofilm was observed after 9 cycles of operation. The relative abundance of Methanobacteriaceae in the microbial community increased from 45.3% (0-15 μm), 57.6% (15-30 μm), 66.9% (30-45 μm) to 77.2% (45-60 μm) within the cathodic biofilm. The methane production rates were positively correlated with the mcrA gene copy numbers in the cathodic biofilm. Our results should be useful to understand the mechanism of methane and hydrogen production in the MEC.
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Affiliation(s)
- Xiao Li
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510006, China
| | - Cuiping Zeng
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510006, China
| | - Yaobin Lu
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510006, China.
| | - Guangli Liu
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510006, China
| | - Haiping Luo
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510006, China
| | - Renduo Zhang
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510006, China
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2
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Menon A, Wang JY, Giannis A. Optimization of micronutrient supplement for enhancing biogas production from food waste in two-phase thermophilic anaerobic digestion. WASTE MANAGEMENT (NEW YORK, N.Y.) 2017; 59:465-475. [PMID: 27765492 DOI: 10.1016/j.wasman.2016.10.017] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Revised: 09/02/2016] [Accepted: 10/11/2016] [Indexed: 06/06/2023]
Abstract
The aim of this study was to enhance the biogas productivity of two-phase thermophilic anaerobic digestion (AD) using food waste (FW) as the primary substrate. The influence of adding four trace metals (Ca, Mg, Co, and Ni) as micronutrient supplement in the methanogenic phase of the thermophilic system was investigated. Initially, Response Surface Methodology (RSM) was applied to determine the optimal concentration of micronutrients in batch experiments. The results showed that optimal concentrations of 303, 777, 7 and 3mg/L of Ca, Mg, Co and Ni, respectively, increased the biogas productivity as much as 50% and significantly reduced the processing time. The formulated supplement was tested in continuous two-phase thermophilic AD system with regard to process stability and productivity. It was found that a destabilized thermophilic AD process encountering high VFA accumulation recovered in less than two weeks, while the biogas production was improved by 40% yielding 0.46L CH4/gVSadded/day. There was also a major increase in soluble COD utilization upon the addition of micronutrient supplement. The results of this study indicate that a micronutrient supplement containing Ca, Mg, Co and Ni could probably remedy any type of thermophilic AD process.
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Affiliation(s)
- Ajay Menon
- Residues and Resource Reclamation Centre (R3C), Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, CleanTech One, Singapore 637141, Singapore
| | - Jing-Yuan Wang
- Residues and Resource Reclamation Centre (R3C), Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, CleanTech One, Singapore 637141, Singapore
| | - Apostolos Giannis
- Residues and Resource Reclamation Centre (R3C), Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, CleanTech One, Singapore 637141, Singapore.
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Mechanical and cell-to-cell adhesive properties of aggregated Methanosarcina. Colloids Surf B Biointerfaces 2015; 126:303-12. [PMID: 25578422 DOI: 10.1016/j.colsurfb.2014.12.035] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Revised: 09/15/2014] [Accepted: 12/19/2014] [Indexed: 11/20/2022]
Abstract
The mechanical and adhesive properties as well as the turgor pressure of microbes play an important role in cell growth and aggregation. By applying AFM together with finite element modelling, one can determine the cell wall structural homogeneity, mechanical and cell-to-cell adhesive properties for aggregated Methanosarcina barkeri cells. This also allows a novel approach to determine in-aggregate turgor pressure determination. Analyzing the AFM force-indentation response of the aggregates under loads less than 10 nN, our study reveals structural inhomogeneity of the polymeric part of the cell wall material and suggests that the cell wall consists of two layers of methanochondroitin (external: with a thickness of 3 ± 1 nm and internal: with a thickness of 169 ± 30 nm). On average, the hyperelastic finite element model showed that the internal layer is more rigid (μ = 14 ± 4 MPa) than the external layer (μ = 2.8 ± 0.9 MPa). To determine the turgor pressure and adhesiveness of the cells, a specific mode of indentation (under a load of 45 nN), aimed towards the centre of the individual aggregate, was performed. By modelling the AFM induced decohesion of the aggregate, the turgor pressure and the cell-to-cell adhesive interface properties could be determined. On average, the turgor pressure is estimated to be 59 ± 22 kPa, the interface strength is 78 ± 12 kPa and the polymer network extensibility is 2.8 ± 0.9 nm. We predict that internal cell wall comprised highly compressed methanochondroitin chains and we are able to identify a conceptual model for stress dependent inner cell wall growth.
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Sowers KR, Boone JE, Gunsalus RP. Disaggregation of Methanosarcina spp. and Growth as Single Cells at Elevated Osmolarity. Appl Environ Microbiol 2010; 59:3832-9. [PMID: 16349092 PMCID: PMC182538 DOI: 10.1128/aem.59.11.3832-3839.1993] [Citation(s) in RCA: 137] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The effect of medium osmolarity on the morphology and growth of Methanosarcina barkeri, Methanosarcina thermophila, Methanosarcina mazei, Methanosarcina vacuolata, and Methanosarcina acetivorans was examined. Each strain was adapted for growth in NaCl concentrations ranging from 0.05 to 1.0 M. Methanosarcina spp. isolated from both marine and nonmarine sources exhibited similar growth characteristics at all NaCl concentrations tested, demonstrating that these species are capable of adapting to a similar range of medium osmolarities. Concomitant with the adaptation in 0.4 to 1.0 M NaCl, all strains disaggregated and grew as single cells rather than in the characteristic multicellular aggregates. Aggregated cells had a methanochondroitin outer layer, while disaggregated single cells lacked the outer layer but retained the protein S-layer adjacent to the cell membrane. Synthesis of glucuronic acid, a major component of methanochondroitin, was reduced 20-fold in the single-cell form of M. barkeri when compared with synthesis in aggregated cells. Strains with the methanochondroitin outer cell layer exhibited enhanced stability at low (<0.2 M NaCl) osmolarity and grew at higher temperatures. Disaggregated cells could be converted back to aggregated cells by gradually readapting cultures to lower NaCl (<0.2 M) and Mg (<0.005 M) concentrations. Disaggregated Methanosarcina spp. could also be colonized and replica plated with greater than 95% recovery rates on solidified agar basal medium that contained 0.4 to 0.6 M NaCl and either trimethylamine, methanol, or acetate as the substrate. The ability to disaggregate and grow Methanosarcina spp. as viable, detergent-sensitive, single cells on agar medium makes these species amenable to mutant selection and screening for genetic studies and enables cells to be gently lysed for the isolation of intact genetic material.
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Affiliation(s)
- K R Sowers
- Department of Microbiology and Molecular Genetics and Molecular Biology Institute, University of California, Los Angeles, 405 Hilgard Avenue, Los Angeles, California 90024
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Xun L, Boone DR, Mah RA. Control of the Life Cycle of Methanosarcina mazei S-6 by Manipulation of Growth Conditions. Appl Environ Microbiol 2010; 54:2064-8. [PMID: 16347717 PMCID: PMC202803 DOI: 10.1128/aem.54.8.2064-2068.1988] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The morphology of Methanosarcina mazei was controlled by magnesium, calcium, and substrate concentrations and by inoculum size; these factors allowed manipulation of the morphology and interconversions between pseudosarcinal aggregates and individual, coccoid cells. M. mazei grew as aggregates in medium with a low concentration of catabolic substrate (either 50 mM acetate, 50 mM methanol, or 10 mM trimethylamine) unless Ca and Mg concentrations were high. Growth in medium high in Ca, Mg, and substrate (i.e., 150 mM acetate, 150 mM methanol, or 40 mM trimethylamine) converted pseudosarcinal aggregates to individual cocci. In such media, aggregates separated into individual cells which continued to grow exclusively as single cells during subsequent transfers. Conversion of single cells back to aggregates was complicated, because conditions which supported the aggregated morphology (e.g., low calcium or magnesium concentration) caused lysis of coccoid inocula. We recovered aggregates from coccoid cells by inoculating serial dilutions into medium high in calcium and magnesium. Cells from very dilute inocula grew into aggregates which disaggregated on continued incubation. However, timely transfer of the aggregates to medium low in calcium, magnesium, and catabolic substrates allowed continued growth as aggregates. We demonstrated the activity of the enzyme (disaggregatase) which caused the dispersion of aggregates into individual cells; disaggregatase was produced not only during disaggregation but also in growing cultures of single cells. Uronic acids, the monomeric constituents of the Methanosarcina matrix, were also produced during disaggregation and during growth as coccoids.
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Affiliation(s)
- L Xun
- Division of Environmental and Occupational Health Sciences, School of Public Health, University of California, Los Angeles, California 90024, and Department of Environmental Science and Engineering, Oregon Graduate Center, 19600 N.W. Von Neumann Drive, Beaverton, Oregon 97006-1999
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Osumi N, Kakehashi Y, Matsumoto S, Nagaoka K, Sakai J, Miyashita K, Kimura M, Asakawa S. Identification of the gene for disaggregatase from Methanosarcina mazei. ARCHAEA (VANCOUVER, B.C.) 2008; 2:185-91. [PMID: 19054745 PMCID: PMC2685598 DOI: 10.1155/2008/949458] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2007] [Accepted: 03/07/2008] [Indexed: 11/18/2022]
Abstract
The gene sequences encoding disaggregatase (Dag), the enzyme responsible for dispersion of cell aggregates of Methanosarcina mazei to single cells, were determined for three strains of M. mazei (S-6(T), LYC and TMA). The dag genes of the three strains were 3234 bp in length and had almost the same sequences with 97% amino acid sequence identities. Dag was predicted to comprise 1077 amino acid residues and to have a molecular mass of 120 kDa containing three repeats of the DNRLRE domain in the C terminus, which is specific to the genus Methanosarcina and may be responsible for structural organization and cell wall function. Recombinant Dag was overexpressed in Escherichia coli and preparations of the expressed protein exhibited enzymatic activity. The RT-PCR analysis showed that dag was transcribed to mRNA in M. mazei LYC and indicated that the gene was expressed in vivo. This is the first time the gene involved in the morphological change of Methanosarcina spp. from aggregate to single cells has been identified.
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Affiliation(s)
- Naoki Osumi
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, Japan
| | - Yoshihiro Kakehashi
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, Japan
- Present address: Kirin Food-Tech Company Ltd., Takasago 676-0028, Japan
| | - Shiho Matsumoto
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, Japan
- Present address: Graduate School of Medicine, University of Tokyo, Minato-ku, Tokyo 108-8639, Japan
| | - Kazunari Nagaoka
- Kyushu National Agricultural Experiment Station, Nishigoshi 861-1192, Japan
- Present address: National Agricultural Research Center, Tsukuba 305-8666, Japan
| | - Junichi Sakai
- Kyushu National Agricultural Experiment Station, Nishigoshi 861-1192, Japan
- Present address: National Agricultural Research Center for Tohoku Region, Morioka 020-0198, Japan
| | - Kiyotaka Miyashita
- National Institute of Agro-environmental Sciences, Tsukuba 305-8604, Japan
| | - Makoto Kimura
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, Japan
| | - Susumu Asakawa
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, Japan
- Kyushu National Agricultural Experiment Station, Nishigoshi 861-1192, Japan
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7
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Evaluation of enzymatic cell treatments for application of CARD-FISH to methanogens. J Microbiol Methods 2008; 72:54-9. [DOI: 10.1016/j.mimet.2007.10.006] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2007] [Revised: 10/11/2007] [Accepted: 10/19/2007] [Indexed: 11/22/2022]
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8
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Pflüger K, Ehrenreich A, Salmon K, Gunsalus RP, Deppenmeier U, Gottschalk G, Müller V. Identification of genes involved in salt adaptation in the archaeonMethanosarcina mazeiGö1 using genome-wide gene expression profiling. FEMS Microbiol Lett 2007; 277:79-89. [DOI: 10.1111/j.1574-6968.2007.00941.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Sørensen AH, Torsvik VL, Torsvik T, Poulsen LK, Ahring BK. Whole-cell hybridization of Methanosarcina cells with two new oligonucleotide probes. Appl Environ Microbiol 1997; 63:3043-50. [PMID: 9251192 PMCID: PMC168603 DOI: 10.1128/aem.63.8.3043-3050.1997] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Two new oligonucleotide probes targeting the 16S rRNA of the methanogenic genus Methanosarcina were developed. The probes have the following sequences (Escherichia coli numbering): probe SARCI551, 5'-GAC CCAATAATCACGATCAC-3', and probe SARCI645, 5'-TCCCGGTTCCAAGTCTGGC-3'. In situ hybridization with the fluorescently labelled probes required several modifications of standard procedures. Cells of Methanosarcina mazeii S-6 were found to lyse during the hybridization step if fixed in 3% formaldehyde and stored in 50% ethanol. Lysis was, however, not observed with cells fixed and stored in 1.6% formaldehyde-0.85% NaCl. Extensive autofluorescence of the cells was found upon hybridization in the presence of 5 mM EDTA, but successful hybridization could be obtained without addition of this compound. The mounting agent Citifluor AF1, often used in conjugation with the fluorochrome fluorescein, was found to wash the labelled probes out of the cells. Stable labelling could be obtained with rhodamine-labelled probes when the specimen was mounted in immersion oil, and high hybridization intensities of the Methanosarcina cells were found even in the presence of biomass from an anaerobic reactor. The inherent high autofluorescence of the biomass could be lowered by use of a highly specific narrow-band filter. The probes were found to be specific for Methanosarcina and useful for detection of this genus in samples from anaerobic reactors.
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Affiliation(s)
- A H Sørensen
- Institute of Environmental Science and Engineering, Technical University of Denmark, Lyngby
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10
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Conway De Macario E, Clarens M, Macario AJ. Archaeal grpE: transcription in two different morphologic stages of Methanosarcina mazei and comparison with dnaK and dnaJ. J Bacteriol 1995; 177:544-50. [PMID: 7836285 PMCID: PMC176626 DOI: 10.1128/jb.177.3.544-550.1995] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Transcription of the heat shock gene grpE was studied in two different morphologic stages of the archaeon Methanosarcina mazei S-6 that differ in resistance to physical and chemical traumas: single cells and packets. While single cells are directly exposed to environmental changes, such as temperature elevations, cells in packets are surrounded by intercellular and peripheral material that keeps them together in a globular structure which can reach several millimeters in diameter. grpE transcript levels determined by Northern (RNA) blotting peaked after a 15-min heat shock in single cells. In contrast, the highest transcript levels in packets were observed after the longest heat shock tested, 60 min. The same response profiles were demonstrated by primer extension experiments and S1 nuclease analysis. A comparison of the grpE response to heat shock with those of dnaK and dnaJ showed that the grpE transcript level was the most increased, closely followed by that of the dnaK transcript, with that of the dnaJ gene being the least augmented. Transcription of grpE started at the same site under normal and heat shock temperatures, and the transcript was consistently approximately 700 bases long. Codon usage patterns revealed that the three archaeal genes use most codons and have the same codon preference for 61% of the amino acids.
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Affiliation(s)
- E Conway De Macario
- Wadsworth Center for Laboratories and Research, New York State Department of Health, Albany
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Conway de Macario E, Macario AJ, Mok T, Beveridge TJ. Immunochemistry and localization of the enzyme disaggregatase in Methanosarcina mazei. J Bacteriol 1993; 175:3115-20. [PMID: 8491727 PMCID: PMC204633 DOI: 10.1128/jb.175.10.3115-3120.1993] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The enzyme disaggregatase (Dag) from Methanosarcina mazei was studied immunochemically. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of purified Dag under reducing and nonreducing conditions revealed a single band with a 94-kDa molecular mass. Dag was found to be immunogenic in rabbits; a polyclonal antibody probe was prepared and used to detect the enzyme by slide immunoenzymatic assay, immunofluorescence, and immunoblotting in various species of Methanosarcina known to convert from packets to single cells, including M. mazei. The enzyme could not be detected in other members of the family Methanosarcinaceae that do not convert. By immunogold electron microscopy, Dag was mapped to the cell wall of packets and to the cell membrane of single cells of two M. mazei strains.
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Affiliation(s)
- E Conway de Macario
- Wadsworth Center for Laboratories and Research, New York State Department of Health, Albany
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12
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Clarens M, Cairó JJ, París JM, Macario AJL, de Macario EC. Characterization and forms of JC3, a newMethanoarcina isolate: Comparison withMethanosarcina mazei strains S-6T MC3, and LYC. Curr Microbiol 1993. [DOI: 10.1007/bf01577373] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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13
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Chapter 16 Structure and function of methanogen genes. ACTA ACUST UNITED AC 1993. [DOI: 10.1016/s0167-7306(08)60265-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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14
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Yao R, Macario AJ, Conway de Macario E. Immunochemical differences among Methanosarcina mazei S-6 morphologic forms. J Bacteriol 1992; 174:4683-8. [PMID: 1624456 PMCID: PMC206264 DOI: 10.1128/jb.174.14.4683-4688.1992] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Methanosarcinae are the only archaeobacteria known to undergo major morphologic changes during growth involving unicellular and multicellular forms, and Methanosarcina mazei S-6 is the only strain for which three distinct forms, packets, single cells, and lamina, have so far been observed. It is reported that two pairs of these forms, either packets and single cells or single cells and lamina, grew and interconverted in medium with the same composition, Ca2+ and Mg2+ concentrations, and growth substrate, and that the two forms in each pair displayed distinctive differences revealed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting, the same growth medium-substrate notwithstanding.
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Affiliation(s)
- R Yao
- Wadsworth Center for Laboratories and Research, New York State Department of Health, Albany
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15
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Schmidt JE, Macario AJ, Ahring BK, Conway de Macario E. Effect of magnesium on methanogenic subpopulations in a thermophilic acetate-degrading granular consortium. Appl Environ Microbiol 1992; 58:862-8. [PMID: 1575487 PMCID: PMC195346 DOI: 10.1128/aem.58.3.862-868.1992] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The effects of Mg2+ on thermophilic (55 degrees C) granules grown on acetate in 0.2-liter upflow anaerobic sludge blanket reactors were studied. The methanogens in the granules were identified and counted by using antibody probes and the antigenic fingerprinting method. Packets of large coccoidal cells antigenically related to Methanosarcina thermophila TM-1 were scarce in the absence of Mg2+ but increased with increasing Mg2+ concentrations up to 30 mM; Methanosarcina packets immunologically related to Methanosarcina barkeri R1M3 showed a similar trend, and their numbers increased up to 100 mM Mg2+. The number of single cells antigenically related to TM-1, R1M3, and Methanosarcina mazei S-6 were scarce at low Mg2+ concentrations but increased drastically at 30 and 100 mM Mg2+. The number of rod-shaped bacteria antigenically related to Methanobacterium thermoautotrophicum GC1 and delta H was highest with no Mg2+ present, and their numbers decreased with increasing concentrations of the cation. These quantitative data, obtained by counting cells in suspensions made from disrupted granules, were confirmed by microscopic observation of the methanogenic subpopulations in thin histologic sections of the granules.
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Affiliation(s)
- J E Schmidt
- Department of Biotechnology, Technical University of Denmark, Lyngby
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16
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Mayerhofer LE, Macario AJ, Conway de Macario E. Lamina, a novel multicellular form of Methanosarcina mazei S-6. J Bacteriol 1992; 174:309-14. [PMID: 1370285 PMCID: PMC205710 DOI: 10.1128/jb.174.1.309-314.1992] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A novel multicellular form of Methanosarcina mazei S-6 is described. It was termed lamina, and it formed during the exponential growth phase when packets or single cells were grown in 40 mM trimethylamine and a total concentration of 8.3 to 15.6 mM Ca2+ and/or Mg2+, in cultures that were not shaken. A distinct molecular event represented by the increment in expression and a spatial redistribution of an antigen during lamina formation is documented.
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Affiliation(s)
- L E Mayerhofer
- Wadsworth Center for Laboratories and Research, New York State Department of Health, Albany
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17
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Xun LY, Mah RA, Boone DR. Isolation and characterization of disaggregatase from Methanosarcina mazei LYC. Appl Environ Microbiol 1990; 56:3693-8. [PMID: 2082820 PMCID: PMC185053 DOI: 10.1128/aem.56.12.3693-3698.1990] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
At certain stages in its growth cycle, Methanosarcina mazei produces an enzyme (disaggregatase) that causes aggregates to separate into single cells. M. mazei S-6 and LYC both produce this enzymatic activity, although the specificities of activities differ. The disaggregatase of M. mazei S-6 had little effect on strain LYC cells, but the disaggregatase of M. mazei LYC disaggregated both strain LYC and strain S-6 cells. The disaggregatase of M. mazei LYC was purified by column chromatography, and it apparently consisted of two similar subunits with a combined molecular size of about 180,000 Da. Strain S-6 culture supernatants contained 14 U of activity per liter when activity was measured as uronic acids released from purified cell wall material. When the activity was quantified as the release of uronic acids from boiled M. mazei S-6 cells, the highest activity was found at pH 4.7 and at 35 degrees C.
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Affiliation(s)
- L Y Xun
- School of Public Health, University of California, Los Angeles 90024
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18
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Knox MR, Harris JE. Isolation and characterization of mutants of mesophilic methanogenic bacteria resistant to analogues of DNA bases and nucleosides. Arch Microbiol 1988. [DOI: 10.1007/bf00446760] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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