• Fisheries and Aquatic Sciences
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• v.17 no.3
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• pp.339-344
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• 2014

PCR amplification with universal primer is a useful tool for speciation of symbionts in marine eukaryote coupled with robust separation method such as denaturing high performance chromatography (DHPLC). To overcome the biased amplification, clamping PCR is recommended to suppress the amplification of host gene. In this study, we evaluated the efficiency of rare gene detection for two kinds of clamping probes which were successfully utilized for eukaryotic symbiont analysis: C3 linked nucleotide (C3) and peptide nucleic acid (PNA). PNA was 3-4 orders of magnitude higher than that of C3 tested in clamping efficiency and rare gene detection. This represented that PNA could be a more competent clamping probe for the enhancement of PCR amplification for rare symbiont genes.

• The Plant Pathology Journal
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• v.38 no.5
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• pp.449-460
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• 2022

This study was performed to reveal phenotypic characters and identity of symbiont bacteria of Nasutitermes as well as investigate their potential as antagonist of plant pathogenic fungi. Isolation of the symbiont bacteria was carried out from inside the heads and the bodies of soldier and worker termite which were collected from 3 locations of nests. Identification was performed using phenotypic test and sequence of 16S ribosomal DNA (16S rDNA). Antagonistic capability was investigated in the laboratory against 3 phytopathogenic fungi i.e., Phytophthora capsici, Ganoderma boninense, and Rigidoporus microporus. Totally, 39 bacterial isolates were obtained from inside the heads and the bodies of Nasutitermes. All the isolates showed capability to inhibit growth of P. capsici, however, 34 isolates showed capability to inhibit growth of G. boninense and 32 isolates showed capability to inhibit growth of R. microporus. Two bacterial strains (IK3.1P and 1B1.2P) which showed the highest percentage of inhibition were further identified based on their sequence of 16S rDNA. The result showed that 1K3.1P strain was placed in the group of type strain and reference strains of Lysinibacillus fusiformis meanwhile 1B1.2P strain was grouped within type strain and reference strains Paenibacillus alvei. The result of this study supply valuable information on the role of symbiont bacteria of Nasutitermes, which may support the development of the control method of the three above-mentioned phytopathogenic fungi.

• KSBB Journal
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• v.14 no.2
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• pp.198-204
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• 1999

Asymbiotic bacterium with highly effective toxins was isolated from entomopathogenic nematode Steinernema glaseri which has been widely used against various soil-inhabiting pests. The symbiont of S. glaseri was identified as Xenorhabdus nematophilus sp. by using several biochemical and physiological tests. When this strain was released into the hemolymph of insect larva, it produced highly toxic substances and killed the larva within 2 days. Two colony forms that differed n some biochemical characteristics were observed when cultures in vitro. Phase l colonies were mucid and difficult to be dispersed in liquid. Phase II was not mucoid and was easily dispersed in liquid. It did not adsorb neutral red or bromothymol blue. Rod-shaped cell size was highly variable between two phases, ranging 2-10 ${\mu}{\textrm}{m}$. It was also found that only infective-stage nematodes can carry only primary-phase Xenorhabdus in their intestine.

• Korean Journal of Microbiology
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• v.27 no.4
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• pp.398-403
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• 1989

The root nodule of Canavalia lineta was classified as a determinate nodule and the symbiont as a Rhizobium-bacteriod based on their morphological characteristics. Isolated encosymbiont was similar both to R. leguminosarum and R. meliloti in its peritrichous arrangement of flagella and some of the physiological characteristics. Compared to control plants, Canavalia seedlings inoculated with the isolate grew normally due to induced root nodules, confirming isolate's infectivity and effectivity. Characteristics of the reisolated endosymbiont from induced root nodule were identical to those of the first isolate, indicating the nodules were induced by the first isolate. From these results, it was confirmed that Rhizobium strain isolated from the root nodules of Canavalia lineata was a real symbiont, and was named Rhizobium sp. SNU003.

• Mycobiology
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• v.51 no.5
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• pp.281-287
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• 2023

The symbiotic association between fungus-gardening termites Macrotermes and its fungal symbiont has a moderate degree of specificity-although the symbiotic fungi (Termitomyces) form a monophyletic clade, there is not a one-to-one association between termite species and their fungus-garden associates. Here, we aim to determine the origin and phylogenetic relationships of Termitomyces in Oman. We used sequences of the internal transcribed spacer region (ITS) and the nuclear large subunit ribosomal RNA (LSU rRNA, 25S) gene and analyzed these with sequences of Termitomyces from other geographic areas. We find no evidence for more than a single colonization of Oman by Termitomyces. Unexpectedly, we find Termitomyces in Oman is most closely related to the symbiont of M. subhyalinus in West Africa rather than to those of geographically closer populations in East Africa.

• Proceedings of the Zoological Society Korea Conference
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• 1997.10b
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• pp.271.1-271
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• 1997

No Abstract, See Full Text

• Proceedings of the Zoological Society Korea Conference
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• 1997.10b
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• pp.271.2-271
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• 1997

No Abstract, See Full Text

• Proceedings of the Zoological Society Korea Conference
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• 2003.08a
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• pp.149.3-149
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• 2003

No Abstract, See Full Text

• Korean Journal of Microbiology
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• v.30 no.4
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• pp.246-251
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• 1992

Molccular cloning of nod genes from Bradvrhizobium sp. SNU001, a nitrogen-fixing symbiont isolated from thc root nodules of soybean (Clycine trim) . was carried out. nod genes were found to be located on thc genome of the symbiont by gcnomic hybridization with 4.5 kb EcoRI/HndIII fragment (nod DABC) of Rhizohium meliloti as probe. Genomic library of this symbiont was constructed using h phage EMBL3-BanlHI vector. from which five nod positive clones were sclectcd by primary and secondary screening methods. The partial restriction map of inserted genomic DNA of h CNS-l(c1one 2) was constructed. and 3.9 kh Bun7HI fragment. which showed strong hybridization signal to the probe, was subcloned into pBS KS(+) plasmid vector. Partial restriction inap ot' a selected subclone (pBjCNS-I) was constructed and nod DABC was found to be located on the 1.8 kb KpnI/Sacl fragment of this subclone.

• BMB Reports
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• v.56 no.1
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• pp.15-23
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• 2023

After birth, animals are colonized by a diverse community of microorganisms. The digestive tract is known to contain the largest number of microbiome in the body. With emergence of the gut-brain axis, the importance of gut microbiome and its metabolites in host health has been extensively studied in recent years. The establishment of organoid culture systems has contributed to studying intestinal pathophysiology by replacing current limited models. Owing to their architectural and functional complexity similar to a real organ, co-culture of intestinal organoids with gut microbiome can provide mechanistic insights into the detrimental role of pathobiont and the homeostatic function of commensal symbiont. Here organoid-based bacterial co-culture techniques for modeling host-microbe interactions are reviewed. This review also summarizes representative studies that explore impact of enteric microorganisms on intestinal organoids to provide a better understanding of host-microbe interaction in the context of homeostasis and disease.