title: β-Galactosidase Langmuir Monolayer at Air/X-gal Subphase Interface.
abstract: This article investigates the surface chemistry properties of the β-galactosidase monolayer at the air-subphase interface at the vicinity of its substrate, X-gal. We have demonstrated that the β-galactosidase in the monolayer form remained active and performed hydrolysis of the X-gal in the subphase. We investigated the β-galactosidase Langmuir monolayer in absence and presence of X-gal in the subphase of varying concentration of X-gal with the sodium chloride solution. It was found that the limiting molecular area as well as the collapse surface pressure kept on decreasing with the increasing concentration of X-gal. In accordance to the data obtained from the isotherm it was also found that β-galactosidase forms a stable monolayer that does not aggregate at the air-subphase interface. The stability of the monolayer at the air-subphase interface was studied by using compression-decompression cycles with and without X-gal at varying concentration and different surface pressures. The infrared reflection-absorption spectroscopy (IRRAS) and Brewster angle microscopy (BAM) of β-galactosidase Langmuir monolayer was also investigated for pure and mixed β-galactosidase at the air-subphase.
authors.affiliation: Department of Chemistry, University of Miami , 1301 Memorial Drive, Coral Gables, Florida 33146, United States.
authors.forename: Shiv K
authors.initials: SK
authors.lastname: Sharma
authors.affiliation: Department of Chemistry, University of Miami , 1301 Memorial Drive, Coral Gables, Florida 33146, United States.
authors.forename: Shanghao
authors.initials: S
authors.lastname: Li
authors.affiliation: MP Biomedicals LLC , 3 Hutton Center, Santa Ana, California 92707, United States.|Department of Engineering Design Technology, Cerritos College , 11110 Alondra Boulevard, Norwalk, California 9265, United States.
authors.forename: Miodrag
authors.initials: M
authors.lastname: Micic
authors.affiliation: MP Biomedicals LLC , 3 Hutton Center, Santa Ana, California 92707, United States.
authors.forename: Jhony
authors.initials: J
authors.lastname: Orbulescu
authors.affiliation: MP Biomedicals SAS, Parc d'innovation-Rue Geiler de Kaysersberg , Illkirch-Graffenstaden 67402, France.
authors.forename: Daniel
authors.initials: D
authors.lastname: Weissbart
authors.affiliation: Department of Biophysical Chemistry, Nagasaki International University , Huis Ten Bosch, Sasebo, Nagasaki 859-3298, Japan.
authors.forename: Hiromichi
authors.initials: H
authors.lastname: Nakahara
authors.affiliation: Department of Biophysical Chemistry, Nagasaki International University , Huis Ten Bosch, Sasebo, Nagasaki 859-3298, Japan.
authors.forename: Osamu
authors.initials: O
authors.lastname: Shibata
authors.affiliation: Department of Chemistry, University of Miami , 1301 Memorial Drive, Coral Gables, Florida 33146, United States.
authors.forename: Roger M
authors.initials: RM
authors.lastname: Leblanc
mesh_terms: D000388:Air; D005697:Galactosides / Q000737:chemistry* / Q000378:metabolism; D007211:Indoles / Q000737:chemistry* / Q000378:metabolism; D012965:Sodium Chloride / Q000737:chemistry; D001616:beta-Galactosidase / Q000737:chemistry* / Q000378:metabolism
chemical_list: D005697:Galactosides; D007211:Indoles; D012965:Sodium Chloride; D001616:beta-Galactosidase; C044888:5-bromo-4-chloro-3-indolyl beta-galactoside