ReviewProtein science : a publication of the Protein Society2012
LacZ β-galactosidase: structure and function of an enzyme of historical and molecular biological importance.
Review in Protein science : a publication of the Protein Society, 2012. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 130 papers.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
130 citing papers in PubMed, 333 citations in OpenAlex.
- Development of a lactose-complemented antibiotic-free host-vector platform for stable enzyme expression in Limosilactobacillus fermentum 217 - 82.World journal of microbiology & biotechnology · 2026Article
- Coengineering Vapor-Deposited Polycationic Microenvironments and Immobilization Strategy to Enhance β‑Galactosidase Kinetics at Acidic pH.ACS omega · 2026Article
- Approaches for Studying Context Specificity of Translation Inhibitor Action.International journal of molecular sciences · 2026Review
- Modular Molecular Design and Self-Assembled Nanostructures of Saccharide‑Appended Cyclic Dipeptides for Glycosidase‑Responsive Supramolecular Hydrogels.Small (Weinheim an der Bergstrasse, Germany) · 2026Article
- Direct Competitive Kinetic Isotope Effect Measurement Using Quantitative Whole Molecule Matrix-Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry.Chembiochem : a European journal of chemical biology · 2026Article
- Usage of nanobody-beta-galactosidase fusion in immunoassays and its application in detecting a peanut allergen.Food chemistry. Molecular sciences · 2026Article
- Galactooligosaccharides Based on β-Galactosidase-Catalyzed Synthesis: Function, Biosynthesis and Optimization Strategy.Foods (Basel, Switzerland) · 2026Review
- Gut microbial-host isozymes: A novel perspective on gut microbiota-host interactions.iScience · 2026Review
- Advances in near-infrared fluorescent probes for the tumor microenvironment.Journal of translational medicine · 2026Review
- Lacto-N-tetraose biosynthesis from lactose via metabolically rewired Escherichia coli.Metabolic engineering · 2026Article
- Structural and functional implications of phase separation of membrane protein LacY in Escherichia coli.Nature communications · 2026Article
- Identification of bacterial key genes and therapeutic targets in hypertensive patients with type 2 diabetes through bioinformatics analysis.Scientific reports · 2026Article
- Evaluating the scientific and regulatory case for the deployment of the radioresistant genusFrontiers in microbiology · 2026Review
- The Role of Protein Side Chains in Enzyme-Activating Conformational Changes: Lessons from Studies on Variant Enzymes.Chemical reviews · 2025Review
- Lactulose selectively stimulates members of the gut microbiota, as determined by multi-modal activity-based sorting.Gut microbes · 2025Article
- Advances in β-Galactosidase Research: A Systematic Review from Molecular Mechanisms to Enzyme Delivery Systems.Pharmaceutics · 2025Review
- Synthesis of an N-Galactosyl Norbornane Aziridine and its Potent Mixed Inhibition of Aspergillus oryzae β-Galactosidase.Chembiochem : a European journal of chemical biology · 2025Article
- Central Roles of Glucosylceramide in Driving Cancer Pathogenesis.International journal of molecular sciences · 2025Review
- Improved Mass Analysis of Proteins and Protein Complexes Present in Common Biological Buffers and Physiological Concentrations of NaCl Using Solution Additives Delivered by Theta Emitters.Analytical chemistry · 2025Article
- Characterization of the ABA receptor PYL gene family and identification of DoPYL1-interacting proteins in Dendrobium officinale.BMC plant biology · 2025Article
70 more citing papers are in PubMed but not listed here.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
3 authors at 2 institutions in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
This review provides an overview of the structure, function, and catalytic mechanism of lacZ β-galactosidase. The protein played a central role in Jacob and Monod's development of the operon model for the regulation of gene expression. Determination of the crystal structure made it possible to understand why deletion of certain residues toward the amino-terminus not only caused the full enzyme tetramer to dissociate into dimers but also abolished activity. It was also possible to rationalize α-complementation, in which addition to the inactive dimers of peptides containing the "missing" N-terminal residues restored catalytic activity. The enzyme is well known to signal its presence by hydrolyzing X-gal to produce a blue product. That this reaction takes place in crystals of the protein confirms that the X-ray structure represents an active conformation. Individual tetramers of β-galactosidase have been measured to catalyze 38,500 ± 900 reactions per minute. Extensive kinetic, biochemical, mutagenic, and crystallographic analyses have made it possible to develop a presumed mechanism of action. Substrate initially binds near the top of the active site but then moves deeper for reaction. The first catalytic step (called galactosylation) is a nucleophilic displacement by Glu537 to form a covalent bond with galactose. This is initiated by proton donation by Glu461. The second displacement (degalactosylation) by water or an acceptor is initiated by proton abstraction by Glu461. Both of these displacements occur via planar oxocarbenium ion-like transition states. The acceptor reaction with glucose is important for the formation of allolactose, the natural inducer of the lac operon.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.