The directed movement of a motile cell or organism, or the directed growth of a cell guided by a specific chemical concentration gradient. Movement may be towards a higher concentration (positive chemotaxis) or towards a lower concentration (negative chemotaxis).

The process in which galactose is transported across a lipid bilayer, from one side of a membrane to the other. D-galactose is widely distributed in combined form in plants, animals and microorganisms as a constituent of oligo- and polysaccharides; it also occurs in galactolipids and as its glucoside in lactose and melibiose.

The directed movement of methylgalactoside into, out of or within a cell, or between cells, by means of some agent such as a transporter or pore. Methylgalactoside is a compound in which the H of the OH group on carbon-1 of galactose is replaced by a methyl group.

The region between the inner (cytoplasmic or plasma) membrane and outer membrane of organisms with two membranes such as Gram negative bacteria. These periplasmic spaces are relatively thick and contain a thin peptidoglycan layer (PGL), also referred to as a thin cell wall.

The region between the inner (cytoplasmic or plasma) membrane and outer membrane of organisms with two membranes such as Gram negative bacteria. These periplasmic spaces are relatively thick and contain a thin peptidoglycan layer (PGL), also referred to as a thin cell wall.