• Parasites, Hosts and Diseases
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• v.32 no.2
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• pp.101-110
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• 1994

This report describes the structures of high-mannose-type N-linked oligosaccharides in glycoproteins synthesized by the microfilariae of Diroflcrio immitis. Microfilariae of D. immitis were incubated in vitro in media containing 2-(3H) mannose to allow metabolic radiolabeling of the oligosaccharide moieties of newly synthesized glycoproteins. Glycopeptides were prepared from the radiolabeled glycoproteins by digestion with pronase and fractionation by chromatography on concanavalin A Sepharose. Thirty eight percent of 2- (3H) mannose incorporated into the microalariae of D. immitis glycopeptides was recovered in high mannose-type asparagine-linked oligosaccharides which were bound to the immobilized lectin. Upon treatment of 2-(3H) mannose labeled glycopeptides with endo - β- N- acetylglu co saminidase H , the high mannose type chains were released and their structures were determined by high performance liquid chromatography and exoglycosidase digestion. The major species of high mannose-type chains synthesized by microfilariae of D. immitis have the composition Man5GlcNAc2, Man6ClcNAc2, Man7GlcNAc2, and Man8GlcNAc2. Structural analyses indicate that these oligosaccharides are similar to high mannose-type chains synthesized by vertebrates.

• Journal of Plant Biology
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• v.33 no.4
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• pp.309-314
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• 1990

Effect of mannose on auxin-induced ethylene production in corn (Zea mays L.) coleoptiles was studied. Auxin induced ethylene production decreased in proportion to mannose concentrations. The inhibitory effect of mannose appeared after 2 h of incubation. Ethylene production was significantly depressed by mannose at high concentration (10-5M-10-4M) of indole acetic acid (IAA), but not at low concentrations (10-8M-10-6M). The inhibition of auxin-induced ethylene production by mannose was specific, since other sugars such as galactose, glucose, sucrose and mannitol did not have an inhibitory effect. In an effort to elucidate mechanisms of mannose the effect on the auxin induced ethylene production, effect of the sugar on ACC synthase activity and ACC induced ethylene production was studied. Mannose failed to inhibit ACC mediated ethylene production, but decreased both the ACC content and ACC synthase activity in the tissue. These results suggest that the inhibitory effect of mannose on auxin induced ethylene production results from suppression of auxin induction of ACC synthase.

• Parasites, Hosts and Diseases
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• v.50 no.4
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• pp.365-369
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• 2012

Acanthamoeba spp. are single-celled protozoan organisms that are widely distributed in the environment. In this study, to understand functional roles of a mannose-binding protein (MBP), Acanthamoeba castellanii was treated with methyl-alpha-D-mannopyranoside (mannose), and adhesion and cytotoxicity of the amoeba were analyzed. In addition, to understand the association of MBP for amoeba phagocytosis, phagocytosis assay was analyzed using non-pathogenic bacterium, Escherichia coli K12. Amoebae treated with mannose for 20 cycles exhibited larger vacuoles occupying the most area of the amoebic cytoplasm in comparison with the control group amoebae and glucose-treated amoebae. Mannose-selected amoebae exhibited lower levels of binding to Chinese hamster ovary (CHO) cells. Exogenous mannose inhibited >50% inhibition of amoebae (control group) binding to CHO cells. Moreover, exogenous mannose inhibited amoebae (i.e., man-treated) binding to CHO cells by <15%. Mannose-selected amoebae exhibited significantly decreased cytotoxicity to CHO cells compared with the control group amoebae, 25.1% vs 92.1%. In phagocytic assay, mannose-selected amoebae exhibited significant decreases in bacterial uptake in comparison with the control group, 0.019% vs 0.03% (P<0.05). Taken together, it is suggested that mannose-selected A. castellanii trophozoites should be severely damaged and do not well interact with a target cell via a lectin of MBP.

• Journal of Plant Biotechnology
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• v.4 no.3
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• pp.129-134
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• 2002

We report the development of a new selection system for the transformation of pepper plants by mannose. In order to achieve this, we first tested several factors related to regeneration conditions. Among the 30 inbred lines examined, line P9l5 was able to generate shoots at the highest rate from both cotyledons and hyporotyls in MS media. A dosage curve for optimizing the selection conditions was established by mixing mannose (range 0-50 g/L) and sucrose (range 0-30 g/L). The least selection pressure on shoot formation was created by a mixture of sucrose and mannose at 20 g/L and 15 g/L, respectively, and the threshold for ultimate tissue death was 50 g/L of mannose irrespective of the sucrose concentration. However, we found that mannose itself was not the sole inhibitor of pepper shoot development. High concentrations of sucrose (30 g/L) contributed additively to the inhibition of shoot formation at higher mannose concentrations. Genotype preference is a major factor that enhances regeneration ability in mannose media, as was observed in MS media. P9l5 and P410 line had high regeneration rates under mannose selection conditions in the presence of Agrobacterium infection. Different virulence levels of Agrobacterium strains did change the regeneration rates, probably due to interaction with the specificities of the inbred lines. Taken together, P9l5 offers the best pepper inbred line for transformation and we recommend a selection condition of 20 g/L of sucrose and 15 g/L or more of mannose up to 50 g/L in media.

• Journal of Photoscience
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• v.1 no.2
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• pp.95-105
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• 1994

Experiments were carried out to investigate whether P, deficiency in detached 25 mM mannose-feeding led to a decline of the photosynthetic electron transport rates through acidification of the thylakoid lumen. With increasing mannose-feeding time, the maximal CO2 exchange rates and the maximal quantum yields of photosynthesis decreased rapidly up to 6 h by 73% then with little decrease up to 12 h. The ATP/ADP ratio declined by 54% 6 h after the treatment and then recovered to the control level at 12 h. However, the NADPH/NADP~ ratio was not significantly altered by mannose treatment. Electron transport rates of thylakoid membranes isolated from 6 h treated leaves did not change, but they decreased by 30% in 12 h treated leaves. The quenching analysis of Chl fluorescence in mannose-treated leaves revealed that both the fraction of reduced plastoquinone and the degree of acidification of thylakoid lumen remained higher than those of the control. The reduction of PSI in mannose fed leaves was inhibited due to acidification of thylakoid lumen (high qE). The reduction of primary quinone acceptor of PSII was inhibited by mannose feeding. Mannose treatment decreased the efficiency of excitation energy capture by PSII. Fo quenching was induced when treated with mannose more than 6 h, and had a reverse linear correlation with (Fv)m/Fm ratio. These results suggest that Pi deficiency in Chinese cabbage leaves reduce photosynthetic electron transport rates by diminishing both PSII function and electron transfer from PSII to PSI through acidification ofthylakoid lumen, which in turn induce the modification of photosynthetic apparatus probably through protein (de)phosphorylation.

• Korean Journal of Microbiology
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• v.25 no.3
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• pp.184-188
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• 1987

Evidences that the mannose permease of Escherichia coli mediates the infection of N4 in early steps, were obtained as follows. First, A mutant strain of Escherichia coli which was resistant to both wild type N4 and lambda whose genome is Charon 4A containing human genomic fragments in its EcoR I site, could not use mannose efficiently. Second, N4 could not infect pel mutant strains which lack one or all of intact components of mannose permease. However, unknown alterations in N4 made it possible for the phage to infect pel mutant of E. coli. It also turned out to be clear that the receptor of N4 was different from that of lambda.

• Journal of Microbiology and Biotechnology
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• v.3 no.1
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• pp.1-5
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• 1993

The gene for mannose enzyme II of phosphoenolpyruvate-dependent phosphotransferase system from Corynebacterium glutamicum KCTC 1445 was cloned into Escherichia coli ZSC113 using plasmid pBR 322. The recombinant plasmid, designated pCTS3, contained 2.2 kb DNA fragment, and the physical map of the cloned DNA fragment was determined. The E. coli ptsM ptsG mutant transformed with pCTS3 restored glucose and mannose fermentation ability, and grew well on these sugars as the sole carbon source in the minimal medium. The transform ant harboring pCTS3 showed a PTS-mediated repression of growth on maltose by mannose analogue, 2-deoxyglucose. The specificity of the response to 2DG therefore indicates that the cloned DNA fragment carries mannose enzyme II gene.

• Journal of Life Science
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• v.21 no.7
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• pp.1060-1066
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• 2011

In order to investigate the variations on the ratio of mannose to galactose in the seeds of Phaseolus angularis, 17 local strains (Yangyang, Pyeongchang, Ganghwa, Pocheon, Geumsan, Seocheon, Jincheon, Danyang, Tongyeong, Sancheong, Gumneung, Wolseong, Wando, Gokseong, Okgu, Jangsu, Bukjeju), which are located from $33^{\circ}15'N$ to $38^{\circ}11'N$, were selected according to their latitudes and geographical distances. The seeds of these strains were collected and their contents of mannose and galactose were analyzed. Mannose contents in the seeds were variable, ranging from 17.071 mg/g at its highest (Jangsu) and 6.488 mg/g at its lowest (Geumsan). The contents of galactose also showed remarkable differences, ranging from 9.477 mg/g (Wolseong) to 19.877 mg/g (Jangsu). The local strains were classified into 3 variation types - coastal type I (Wando, Okgu, Bukjeju), the inland type (Jangsu, Weolseong, Danyang, Geumneung, Pyeongchang, Sancheong) and coastal type II (Ganghwa, Seocheon, Tongyeong, Jincheon), as well as 4 strange strains (Gokseong, Yangyang, Pocheon, Geumsan) according to the geographical climatic type and the ratio of mannose to galactose, which indicate the hardness of seeds in Leguminosae and ranged from 0.64 to 1.22. The variation types are very significant genecologically as evidence for microevolution related to natural and artificial selection in cultivated plants.

• The Korean Journal of Ecology
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• v.28 no.3
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• pp.157-161
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• 2005

In order to investigate the geographical variation of Glycine soja distributed in southern area of Korean peninsula, 8 local populations(Sokcho, Wonju, Mt. Chiak, Cheongju, Andong, Taegu, Ulsan, Sacheon), which located from $34^{\circ}50'00"N$ to $38^{\circ}12'00"N$, were selected according to their latitudes and geographical distances. The seeds of these populations were collected and their contents of mannose and galactose were investigated, Mannose contents in the seeds were variable in the range between the highest 460.00 mg/g (Andong) and the lowest 55.23 mg/g(Sacheon). The contents of galactose were represented remarkable differences from 67.17 mg/g(Sacheon) to 387.50 mg/g(Ulsan) also. The local populations were classified into 3 types such as the middle southern inland type (Andong, Taegu), the middle northern type(Wonju, Mt. Chiak, Cheongju) and the coastal type(Sokcho, Ulsan, Sacheon) according to the ratio of mannose and galactose, which indicate the hardness of seeds in Leguminosae, ranged from 0.41 to 1.73. Particularly, those of middle southern inland populations represented the high values compared with those of other populations.

• Journal of Crop Science and Biotechnology
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• v.11 no.4
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• pp.233-236
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• 2008

A positive selectable marker system was adapted for transformation of mature embryo-derived calli of Indica rice (Oryza sativa L.) utilizing the PMI gene encoding for phosphomannose-isomerase that converts mannose-6-phosphate to fructose-6-phosphate. The transformed cells grew on medium supplemented with 3% mannose as carbon source and calli were selected on media containing various concentrations of mannose. Molecular analyses showed that the transformed plants contained the PMI gene. The results indicate that the mannose selection system can be used for Agrobacterium-mediated transformation of mature embryo in rice to substitute the use of conventional selectable markers in genetic transformation.