What is the molecular weight of beta-galactosidase?
The amino acid sequence of beta-galactosidase was determined. The protein contains 1021 amino acid residues in a single polypeptide chain. The subunit molecular weight calculated from the sequence is 116,248.
What is beta-galactosidase made up of?
β-Galactosidase is basically a tetramer of four identical polypeptide chains with each chain consisting of 1023 amino acids which combine to form five well-defined structural domains.
What is the structure of beta-galactosidase?
Beta-galactosidase consists of four chains, each with 1023 amino acids (blue), that form four active sites. The substrate/product allolactose (pink and white) can be seen here in two of these active sites. This structure is based on a high resolution (1.5 Angstrom) x-ray crystallographic study.
What is the size of beta-galactosidase?
The dimensions of the β-galactosidase tetramer are ∼180 Å x 140 Å x 87 Å.
What type of enzyme is β galactosidase?
glycoside hydrolase enzymes
β-galactosidase, also called lactase, beta-gal or β-gal, is a family of glycoside hydrolase enzymes that catalyzes the hydrolysis of β-galactosides into monosaccharides through the breaking of a glycosidic bond.
What is the molecular weight of LDH?
144,000 daltons
Lactate dehydrogenase is usually regarded as a tetramer of a molecular weight of 144,000 daltons, which is equivalent to 144,000 g/mol. It is composed of four subunits with a molecular weight 36,000 daltons each.
How is beta-galactosidase made?
The presence of lactose results in the synthesis of allolactose which binds to the lac repressor and reduces its affinity for the lac operon. This in turn allows the synthesis of β-galactosidase, the product of the lacZ gene.
What class of enzyme is β-galactosidase?
class 3
The EC (Enzyme Commission) number of β-galactosidase is 3.2. 1.23 β-galactosidase belongs to class 3, which refers to the hydrolases. β-gal belongs to a sub-class of glycosylases with an oxygen substrate nature.
Is beta-galactosidase A protein?
β-Galactosidase, as proteins in general, forms crystals that include about 50% protein and 50% solvent by volume.
What is the size of the lacZ gene?
about 3kb
The lacZ gene is about 3kb and the largest product that is seen on the gel is about 700bp.
How many subunits does beta-galactosidase have?
four identical subunits
β-Gal has a molecular weight of 540,000 and is composed of four identical subunits of MW 135,000, each with an independent active site (Melcher and Messer, 1973) (Figure 22.3).
What is the molecular weight of lactic acid?
90.08 g/molLactic acid / Molar mass
How many amino acids are in LDH?
Lactate dehydrogenase(LDH) is an enzyme that catalyzes the interconversion of pyruvate and lactate and the associated conversion of NADH to NAD+ (refer to Image 1.) (12) It has a molecular weight of 35735.44 g/mol, an isoelectric point of 7.12 and a 322 residue amino acid sequence within one chain ( Chain A) (2.)
Is lacZ the same as beta-galactosidase?
coli, the lacZ gene is the structural gene for β-galactosidase; which is present as part of the inducible system lac operon which is activated in the presence of lactose when glucose level is low. β-galactosidase synthesis stops when glucose levels are sufficient.
How many base pairs is the lacZ gene?
Abstract. The lac operon of Escherichia coli spans approximately 5300 base pairs and includes the lacZ, lacY, and lacA genes in addition to the operator, promoter, and transcription termination regions.
How is beta-galactosidase activity measured?
β-Galactosidase converts the colorless ONPG substrate into galactose and the chromophore o-nitrophenol, yielding a bright yellow solution. The β-galactosidase activity of the solution can be quantitated using a spectrophotometer or a microplate reader to determine the amount of substrate converted at 420 nm.
How many carbon are present in lactic acid?
As per the molecular formula of this compound, the IUPAC name of lactic acid is 2-hydroxypropanoic acid. The IUPAC name helps us to find out the molecular formula without any hassle. It is easy to conclude that the molecular formula contains three carbon atoms.
What amino acids are in LDH?
LDH-X is clearly distinct in amino acid composi- tion from LDH-1 and LDH-5 with respect to numbers of residues of leucine, glycine, threonine, and methionine.