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Ganglioside-magnetosome complex formation enhances uptake of gangliosides by cells.

Guan F, Li X, Guo J, Yang G, Li X - Int J Nanomedicine (2015)

Bottom Line: The use of GM1-magnetosome complex resulted in the greatest enhancement of ganglioside incorporation by cells.GM3-magnetosome complex significantly inhibited EGF-induced phosphorylation of the epidermal growth factor receptor.Both of these effects were further enhanced by the presence of a magnetic field.

View Article: PubMed Central - PubMed

Affiliation: The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, People's Republic of China.

ABSTRACT
Bacterial magnetosomes, because of their nano-scale size, have a large surface-to-volume ratio and are able to carry large quantities of bioactive substances such as enzymes, antibodies, and genes. Gangliosides, a family of sialic acid-containing glycosphingolipids, function as distinctive cell surface markers and as specific determinants in cellular recognition and cell-to-cell communication. Exogenously added gangliosides are often used to study biological functions, transport mechanisms, and metabolism of their endogenous counterparts. Absorption of gangliosides into cells is typically limited by their tendency to aggregate into micelles in aqueous media. We describe here a simple strategy to remove proteins from the magnetosome membrane by sodium dodecyl sulfate treatment, and efficiently immobilize a ganglioside (GM1 or GM3) on the magnetosome by mild ultrasonic treatment. The maximum of 11.7±1.2 µg GM1 and 11.6±1.5 μg GM3 was loaded onto 1 mg magnetosome, respectively. Complexes of ganglioside-magnetosomes stored at 4°C for certain days presented the consistent stability. The use of GM1-magnetosome complex resulted in the greatest enhancement of ganglioside incorporation by cells. GM3-magnetosome complex significantly inhibited EGF-induced phosphorylation of the epidermal growth factor receptor. Both of these effects were further enhanced by the presence of a magnetic field.

No MeSH data available.


Related in: MedlinePlus

Characteristics of ganglioside-magnetosome complex.Notes: (A) The protein released from magnetosome with SDS treatment for 30 seconds, 1, 3, 5, 7 and 10 minutes was determined by BCA assay. (B) FT-IR spectra of magnetosomes before and after SDS treatment. (Ci) Equivalent amounts of control magnetosomes (lane 1), SDS-treated magnetosomes (lane 2), GM1-magnetosomes (lane 3), and GM3-magnetosomes (lane 4) were extracted, subjected to HPTLC, and visualized as described in M&M/“high-performance thin layer chromatography”. Equivalent amounts of GM1-magnetosomes (Cii) or GM3-magnetosomes (Ciii) stored at 4°C for 2 (shown as 2d), 4 (4d), 6 (6d), and 8 (8d) days were extracted, subjected to HPTLC, and visualized as described in M&M/“high-performance thin layer chromatography”. (D) TEM imaging of four types of magnetosomes as in (B). Upper row: 200,000× magnification. Scale bar =50 nm. Lower row: close-ups of images in upper row.Abbreviations: BCA, bicinchoninic acid; FT-IR, Fourier-transform infrared spectroscopy; HPTLC, high-performance thin layer chromatography; M&M, materials and methods; SDS, sodium dodecyl sulfate; TEM, transmission electron microscopy.
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f2-ijn-10-6919: Characteristics of ganglioside-magnetosome complex.Notes: (A) The protein released from magnetosome with SDS treatment for 30 seconds, 1, 3, 5, 7 and 10 minutes was determined by BCA assay. (B) FT-IR spectra of magnetosomes before and after SDS treatment. (Ci) Equivalent amounts of control magnetosomes (lane 1), SDS-treated magnetosomes (lane 2), GM1-magnetosomes (lane 3), and GM3-magnetosomes (lane 4) were extracted, subjected to HPTLC, and visualized as described in M&M/“high-performance thin layer chromatography”. Equivalent amounts of GM1-magnetosomes (Cii) or GM3-magnetosomes (Ciii) stored at 4°C for 2 (shown as 2d), 4 (4d), 6 (6d), and 8 (8d) days were extracted, subjected to HPTLC, and visualized as described in M&M/“high-performance thin layer chromatography”. (D) TEM imaging of four types of magnetosomes as in (B). Upper row: 200,000× magnification. Scale bar =50 nm. Lower row: close-ups of images in upper row.Abbreviations: BCA, bicinchoninic acid; FT-IR, Fourier-transform infrared spectroscopy; HPTLC, high-performance thin layer chromatography; M&M, materials and methods; SDS, sodium dodecyl sulfate; TEM, transmission electron microscopy.

Mentions: Removal of the proteins from the magnetosome membrane by SDS treatment is the first step to generate the ganglioside-magnetosome complexes. The released protein from magnetosome after SDS treatment was examined by the bicinchoninic acid method (Figure 2A). The highest concentration of released protein in the supernatant was reached in 5 minutes after SDS treatment. The membranes of SDS-treated and -untreated magnetosomes were then characterized by Fourier-transform infrared spectroscopy. SDS-treated magnetosomes showed lower signals of amide I at 1,656 cm−1 (from C=O stretching vibration), amide II at 1,537 cm−1 (from N–H bending vibration and C–N stretching vibration), and NH bending vibration at 3,282 cm−1 (Figure 2B).22 These findings indicate that most proteins on the magnetosomes were removed successfully.


Ganglioside-magnetosome complex formation enhances uptake of gangliosides by cells.

Guan F, Li X, Guo J, Yang G, Li X - Int J Nanomedicine (2015)

Characteristics of ganglioside-magnetosome complex.Notes: (A) The protein released from magnetosome with SDS treatment for 30 seconds, 1, 3, 5, 7 and 10 minutes was determined by BCA assay. (B) FT-IR spectra of magnetosomes before and after SDS treatment. (Ci) Equivalent amounts of control magnetosomes (lane 1), SDS-treated magnetosomes (lane 2), GM1-magnetosomes (lane 3), and GM3-magnetosomes (lane 4) were extracted, subjected to HPTLC, and visualized as described in M&M/“high-performance thin layer chromatography”. Equivalent amounts of GM1-magnetosomes (Cii) or GM3-magnetosomes (Ciii) stored at 4°C for 2 (shown as 2d), 4 (4d), 6 (6d), and 8 (8d) days were extracted, subjected to HPTLC, and visualized as described in M&M/“high-performance thin layer chromatography”. (D) TEM imaging of four types of magnetosomes as in (B). Upper row: 200,000× magnification. Scale bar =50 nm. Lower row: close-ups of images in upper row.Abbreviations: BCA, bicinchoninic acid; FT-IR, Fourier-transform infrared spectroscopy; HPTLC, high-performance thin layer chromatography; M&M, materials and methods; SDS, sodium dodecyl sulfate; TEM, transmission electron microscopy.
© Copyright Policy
Related In: Results  -  Collection

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f2-ijn-10-6919: Characteristics of ganglioside-magnetosome complex.Notes: (A) The protein released from magnetosome with SDS treatment for 30 seconds, 1, 3, 5, 7 and 10 minutes was determined by BCA assay. (B) FT-IR spectra of magnetosomes before and after SDS treatment. (Ci) Equivalent amounts of control magnetosomes (lane 1), SDS-treated magnetosomes (lane 2), GM1-magnetosomes (lane 3), and GM3-magnetosomes (lane 4) were extracted, subjected to HPTLC, and visualized as described in M&M/“high-performance thin layer chromatography”. Equivalent amounts of GM1-magnetosomes (Cii) or GM3-magnetosomes (Ciii) stored at 4°C for 2 (shown as 2d), 4 (4d), 6 (6d), and 8 (8d) days were extracted, subjected to HPTLC, and visualized as described in M&M/“high-performance thin layer chromatography”. (D) TEM imaging of four types of magnetosomes as in (B). Upper row: 200,000× magnification. Scale bar =50 nm. Lower row: close-ups of images in upper row.Abbreviations: BCA, bicinchoninic acid; FT-IR, Fourier-transform infrared spectroscopy; HPTLC, high-performance thin layer chromatography; M&M, materials and methods; SDS, sodium dodecyl sulfate; TEM, transmission electron microscopy.
Mentions: Removal of the proteins from the magnetosome membrane by SDS treatment is the first step to generate the ganglioside-magnetosome complexes. The released protein from magnetosome after SDS treatment was examined by the bicinchoninic acid method (Figure 2A). The highest concentration of released protein in the supernatant was reached in 5 minutes after SDS treatment. The membranes of SDS-treated and -untreated magnetosomes were then characterized by Fourier-transform infrared spectroscopy. SDS-treated magnetosomes showed lower signals of amide I at 1,656 cm−1 (from C=O stretching vibration), amide II at 1,537 cm−1 (from N–H bending vibration and C–N stretching vibration), and NH bending vibration at 3,282 cm−1 (Figure 2B).22 These findings indicate that most proteins on the magnetosomes were removed successfully.

Bottom Line: The use of GM1-magnetosome complex resulted in the greatest enhancement of ganglioside incorporation by cells.GM3-magnetosome complex significantly inhibited EGF-induced phosphorylation of the epidermal growth factor receptor.Both of these effects were further enhanced by the presence of a magnetic field.

View Article: PubMed Central - PubMed

Affiliation: The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, People's Republic of China.

ABSTRACT
Bacterial magnetosomes, because of their nano-scale size, have a large surface-to-volume ratio and are able to carry large quantities of bioactive substances such as enzymes, antibodies, and genes. Gangliosides, a family of sialic acid-containing glycosphingolipids, function as distinctive cell surface markers and as specific determinants in cellular recognition and cell-to-cell communication. Exogenously added gangliosides are often used to study biological functions, transport mechanisms, and metabolism of their endogenous counterparts. Absorption of gangliosides into cells is typically limited by their tendency to aggregate into micelles in aqueous media. We describe here a simple strategy to remove proteins from the magnetosome membrane by sodium dodecyl sulfate treatment, and efficiently immobilize a ganglioside (GM1 or GM3) on the magnetosome by mild ultrasonic treatment. The maximum of 11.7±1.2 µg GM1 and 11.6±1.5 μg GM3 was loaded onto 1 mg magnetosome, respectively. Complexes of ganglioside-magnetosomes stored at 4°C for certain days presented the consistent stability. The use of GM1-magnetosome complex resulted in the greatest enhancement of ganglioside incorporation by cells. GM3-magnetosome complex significantly inhibited EGF-induced phosphorylation of the epidermal growth factor receptor. Both of these effects were further enhanced by the presence of a magnetic field.

No MeSH data available.


Related in: MedlinePlus