• Korean Journal of Soil Science and Fertilizer
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• v.43 no.1
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• pp.96-104
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• 2010

A comparative study was performed in gnotobiotic and greenhouse conditions to evaluate the effect of exogenous application of indole-3-acetic acid (IAA) and inoculation of Methylobacterium spp. possessing 1-aminocyclopropane-1-carboxylate deaminase (ACCD) and IAA activity on red pepperand tomato seedling growth and development. Application of 1.0 ${\mu}g\;mL^{-1}$ IAA positively influenced root growth while high concentrations (>10.0 ${\mu}g\;mL^{-1}$) suppressed root growth of red pepper and tomato under gnotobiotic condition. On the other hand, inoculation of Methylobacterium strains with ACCD activity and IAA or without IAA enhanced root growth in both plants. Similarly, under greenhouse condition the inoculation of Methylobacterium sp. with ACCD activity and IAA enhanced plant fitness recorded as average nodal length and specific leaf weight (SLW) but the effect is comparable with the application of low concentrations of IAA. Seedling length was significantly increased by Methylobacterium strains while total biomass was enhanced by Methylobacterium spp. and exogenous applications of < 10.0 ${\mu}g\;mL^{-1}$ IAA. High concentrations of IAA retard biomass accumulation in red pepper and tomato. These results confirm that bacterial strains with plant growth promoting characters such as IAA and ACCD have characteristic effects on different aspects of growth of red pepper and tomato seedlings which is comparable or better than exogenous applications of synthetic IAA.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.1
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• pp.37-42
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• 2012

Improvement of plant growth by Methylotrophic bacteria can be influenced through alterations in growth modulating enzymes or hormones, especially by decreasing ethylene levels enzymatically by 1-aminocyclopropane-1-carboxylate (ACC) deaminase or by production of indole-3-acetic acid (IAA). In this study, the effect of seven strains of Methylobacterium on seedling ethylene emission of tomato and red pepper plants was evaluated under greenhouse condition. Ethylene emission was lowest in Methylobacterium oryzae CBMB20 inoculated tomato plants and CBMB110 inoculated red pepper plants at 47 days after sowing (DAS). However, at 58 DAS all inoculated plants showed almost similar pattern of ethylene emission. Methylobacterium inoculated tomato and red pepper plants showed significantly less ethylene emission compared to control. Our results demonstrated that Methylobacterium spp. inoculation promotes plant growth due to the reduction of ethylene emission and therefore can be potentially used in sustainable agriculture production systems.

• Korean Journal of Environmental Agriculture
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• v.41 no.2
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• pp.115-124
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• 2022

BACKGROUND: Methane is a major greenhouse gas attributed to global warming partly contributed by agricultural activities from ruminant fermentation and rice paddy fields. Methanotrophs are microorganisms that utilize methane. Their unique metabolic lifestyle is enabled by enzymes known as methane monooxygenases (MMOs) catalyzing the oxidation of methane to methanol. Rice absorbs, transports, and releases methane directly from soil water to its stems and the micropores and stomata of the plant epidermis. Methylobacterium species associated with rice are dependent on their host for metabolic substrates including methane. METHODS AND RESULTS: Methylobacterium spp. isolated from rice were evaluated for methane oxidation activities and screened for the presence of sMMO mmoC genes. Qualitatively, the soluble methane monooxygenase (sMMO) activities of the selected strains of Methylobacterium spp. were confirmed by the naphthalene oxidation assay. Quantitatively, the sMMO activity ranged from 41.3 to 159.4 nmol min^-1 mg of protein^-1. PCR-based amplification and sequencing confirmed the presence and identity of 314 bp size fragment of the mmoC gene showing over 97% similarity to the CBMB27 mmoC gene indicating that Methylobacterium strains belong to a similar group. CONCLUSION(S): Selected Methylobacterium spp. contained the sMMO mmoC gene and possessed methane oxidation activity. As the putative methane oxidizing strains were isolated from rice and have PGP properties, they could be used to simultaneously reduce paddy field methane emission and promote rice growth.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.4
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• pp.266-287
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• 2004

The non infecting, plant associated bacteria have attracted increased attention for stimulating plant growth and as environmental friendly plant protecting agents. Pink-pigmented facultatively methylotrophic bacteria (PPFMs), classified as Methylobacterium spp., are persistent colonizers of plant leaf surfaces. As the leaves of most or all plants harbor PPFMs that utilize leaf methanol as their sole source of carbon and energy, which is a specific attribute of the genus Methylobacterium. Although they are not well known, these bacteria are co-evolved, interacting partners in plant metabolism. This claim is supported, for example, by the following observations: (1) PPFMs are seed-transmitted, (2) PPFMs are frequently found in putatively axenic cell cultures, (3) Low numbers of seed-borne PPFMs correlate with low germinability, (4) Plants with reduced numbers of PPFM show elevated shoot/root ratios, (5) Foliar application of PPFMs to soybean during pod fill enhances seed set and yield, (6) Liverwort tissue in culture requires PPFM-produced vitamin B12 for growth, (7) treated plants to suppress or decrease disease incidence of sheath blight caused by Rhizoctonia solani in rice, and (8) the PPFM inoculation induced number of stomata, chlorophyll concentration and malic acid content, they led to increased photosynthetic activity. Methylobacterium spp. are bacterial symbionts of plants, shown previously to participate in plant metabolism by consuming plant waste products and producing metabolites useful to the plant. There are reports that inform about the beneficial interactions between this group of bacteria and plants. Screening of such kind of bacteria having immense plant growth promoting activities like nitrogen fixation, phytohormone production, alleviating water stress to the plants can be successfully isolated and characterized and integration of such kind of organism in crop production will lead to increased productivity.

• Journal of Microbiology and Biotechnology
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• v.16 no.10
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• pp.1622-1628
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• 2006

Bacteria from the Methylobacterium genus, called pink-pigmented facultative methylotrophic bacteria (PPFMs), are common inhabitants of plants, potentially dominating the phyllosphere population, and are also encountered in the rhizosphere, seeds, and other parts of plants, being versatile in nature. The consistent success of the Methylobacterium plant association relies on methylotrophy, the ability to utilize the one-carbon compound methanol emitted by plants. However, the efficiency of Methylobacterium in plant growth promotion could be better exploited and thus has attracted increasing interest in recent years. Accordingly, the present study investigated the inoculation effects of Methylobacterium sp. strains CBMB20 and CBMB 110 on seed imbibition to tomato and red pepper on the growth and accumulation of phytohormone levels under gnotobiotic conditions. Seeds treated with the Methylobacterium strains showed a significant increase in root length when compared with either the uninoculated control or Methylobacterium extorquens $miaA^-$ knockout mutanttreated seeds. Extracts of the plant samples were used for indole-3-acetic acid (IAA), trans-zeatin riboside (t-ZR), and dihydrozeatin riboside (DHZR) assays by immunoanalysis. The treatment with Methylobacterium sp. CBMB20 or CBMB 110 produced significant increases in the accumulation of IAA and the cytokinins t-ZR and DHZR in the red pepper extracts, whereas no IAA was detected in the tomato extracts, although the cytokinin concentrations were significantly increased. Therefore, this study proved that the versatility of Methylobacterium as a plant-growth promoting bacteria could be better exploited.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2016.11a
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• pp.118.2-118.2
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• 2016

몇몇의 박테리아들은 바이오필름을 형성하여 그들 스스로를 보호한다. 하지만 바이오필름으로 인해 악취와 질병 등의 문제가 많이 발생되고 있기 때문에 바이오필름을 형성하는 박테리아의 성장을 효율적으로 억제하기 위해 은 나노, 구리 나노입자들이 포함된 다양한 나노스케일의 재료들에 대한 연구가 활발히 진행되어오고 있다. 이들 연구의 주된 목표는 체내에서 독성은 나타내지 않으면서 항균성을 증가시키는 것에 있다. 특히, 구형으로 이루어진 나노입자와 높은 종횡비를 가지는 탄소나노튜브와 같이 차원이 다른 나노물질들의 복합체들은 세포독성을 최소화하면서 특정 박테리아에 대한 항균성을 향상시킬지도 모른다. 이번 연구에서는, 산 처리된 탄소나노튜브에 화학적인 방법을 이용하여 구리 이온을 각각 환원시켜 구리 나노-탄소나노튜브 복합체를 합성하였다. 이들 복합체는 transmission electron microscopy, X-ray diffractometry, energy-dispersive X-ray spectroscopy 를 이용하여 특성이 분석되었고 Methylobacterium spp., Sphingomonas spp. 와 E. coli 에 대하여 항균성이 평가되었다. 추가적으로 구리 나노-탄소나노튜브 복합체는 human fibroblast cells 에 대하여 세포독성이 평가되었고 제작된 마이크로칩 안에 형성된 바이오필름의 성장억제효과가 평가되었다. 결과적으로, 구리 나노-탄소나노튜브 복합체에서 바이오필름을 형성하는 Methylobacterium spp. 에 대하여 특이적으로 항균성을 나타냈으며 바이오필름이 형성된 마이크로칩에서 바이오필름을 제거 하는 것이 확인되었다.

• Journal of Digital Convergence
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• v.15 no.6
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• pp.339-344
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• 2017

In this study, microorganisms were isolated from nosocomial environment and are identified by biochemical analysis as the part of biochemical and technical convergence. Microorganisms were collected at intense care unit of general hospital located in Pyeongtak (2014.11.28. - 2014. 11. 30). Using a VITEK2 equipment of biochemical approaches, eleven microorganisms e.g., Micrococcus luteus (or M. lylae), Granulicatella adiacens (M. luteus or M. lylae), Staphylococcus caprae, Sphingomonas paucimobilis, Kocuria kristinae, G elegans, Aerococcus viridans (or Staphylococcus arlettae), Methylobacterium spp., Dermacoccus nishinomiyaensis (or Kytococcus sedentarius), Kocuria kristinae (or M. luteus, M. lylae), Pseudomonas oryzihabitans were identified. And then identified bacteria plates were applied with a plastic stick, so called with "FarmeTok (medistick/Puristic) to produce ClO2. ClO2-releasing plastic stick showed the very strong inhibition of bacterial growth with about 99.9%. There were no bacterial colonies on the ClO2-incubated plate. Taken together, it is suggested that chlorine dioxide should be very strong inhibitor to microorganisms of nosocomial infections.

• The Plant Pathology Journal
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• v.24 no.1
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• pp.74-79
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• 2008

This research was conducted to evaluate fungal and bacterial populations in unhulled and brown rice under indoor storage conditions, and to examine the relationship between microbial populations and environmental conditions such as temperature and relative humidity. The temperature and relative humidity of the storage room ranged from $22.6^{\circ}C\;to\;27.0^{\circ}C$ and 23.3% to 44.2%, respectively. Total fungal and bacterial populations remained relatively stable over the storage period. Predominant fungi included Aspergillus candidus, A. flavus, A. fumigatus, and Penicillium spp.; the predominant bacteria were Bacillus, Microbacterium, Sphingomonas, and Methylobacterium spp. Total fungi and bacteria were not significantly correlated with either unhulled (r=0.448, P=0.372) or brown (r=0.466, P=0.351) rice. In unhulled rice, total fungi showed positive correlations with total Aspergillus (r=0.994, P<0.001) and total Penicillium (r=0.906, P<0.05); A. flavus was positively correlated with total Aspergillus (r=0.913, P<0.05) and total fungi (r=0.868, P<0.05). In brown rice, Bacillus spp. was also positively correlated with total bacteria (r=0.998, P<0.001). Mean temperature was negatively correlated with A. candidus (r=-0.852, P<0.05) and total fungi (r=-0.961, P<0.01), and mean relative humidity was positively correlated with total Penicillium spp.(r=0.884, P<0.05) in brown rice. Hence these results could provide basic information on the fungal and bacterial populations in unhulled and brown rice stored under room conditions, and on the effect of environmental conditions on the populations of fungi and bacteria, especially Aspergillus and Penicillium spp.