RESUMEN
Living microalgal cells differ from other cells that are used as objects for optical micromanipulation, in that they have strong light absorption in the visible range, and by the fact that their reaction centers are susceptible to photodamage. We trapped cells of the microalga Trachydiscus minutus using optical tweezers with laser wavelengths in the range from 735 nm to 1064 nm. The exposure to high photon flux density caused photodamage that was strongly wavelength dependent. The photochemical activity before and after exposure was assessed using a pulse amplitude modulation (PAM) technique. The photochemical activity was significantly and irreversibly suppressed by a 30s exposure to incident radiation at 735, 785, and 835 nm at a power of 25 mW. Irradiance at 885, 935 and 1064 nm had negligible effect at the same power. At a wavelength 1064 nm, a trapping power up to 218 mW caused no observable photodamage.
Asunto(s)
Microalgas/efectos de la radiación , Pinzas Ópticas , Fotólisis , Células CultivadasRESUMEN
A method for the elution of glycoproteins from sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) replicas of gels on polyvinylidene difluoride (PVDF) membranes is described. Ten model glycoproteins were resolved by SDS-PAGE and then electrotransferred onto PVDF membranes. After reversible staining, glycoprotein bands were eluted with a mixture of SDS/Triton X-100 at pH 9 or with a mixture of guanidinium hydrochloride/lysophosphatidylcholine at neutral pH. For both types of eluents, the final recoveries ranged from over 30% to about 80%. Good recoveries and mild conditions of elution render the method applicable for the structural elucidation of glycan chains.
Asunto(s)
Resinas Acrílicas , Electroforesis en Gel de Poliacrilamida/métodos , Glicoproteínas/aislamiento & purificación , Animales , Bovinos , Humanos , Membranas Artificiales , Polivinilos , Dodecil Sulfato de SodioRESUMEN
The paper describes the procedure of efficient elution of glycoproteins from Immobilon membrane after their blotting from polyacrylamide gel. The yield of elution from membrane is 30-70%.