Values CatLog read from this paper
The beta-galactosidase (Escherichia coli) reaction is partly facilitated by interactions of His-540 with the C6 hydroxyl of galactose
PMID 8662937doi:10.1074/jbc.271.24.14296Open in Browse
The paper itself is not on this site: read it at the publisher. This page lists only the values CatLog read from it.
CatLog read 44 records (80 values) from this paper: β-galactosidase from Escherichia coli.
Read from the paper by an AI model and checked against the paper by a second, separate AI run; code converted the units. Values are in CatLog's units; each record opens in Browse with the line the paper prints and the checks. CatLog calculated the 4 kcat/Km values marked “calc.” from kcat and Km; no printed kcat/Km was read for those records.
| Enzyme | Organism | Substrate | kcat (s⁻¹) | Km (mM) | kcat/Km (mM⁻¹ s⁻¹) | Conditions | Open record |
|---|---|---|---|---|---|---|---|
| β-galactosidase | Escherichia coli | 2-nitrophenyl beta-D-galactopyranoside1 mM Mg2+; continuous assay at 420 nm | 620 | 0.12 | 5.2 × 10³ | pH 7, 25 °C | Open record: β-galactosidase, 2-nitrophenyl beta-D-galactopyranoside |
| β-galactosidase | Escherichia coli | 2-nitrophenyl beta-D-galactopyranosideno Mg2+ (Mg2+ omitted, 10 mM EDTA) | 39 | 0.57 | 68 calc. | pH 7, 25 °C | Open record: β-galactosidase, 2-nitrophenyl beta-D-galactopyranoside |
| β-galactosidase | Escherichia coli | 4-nitrophenyl alpha-L-arabinopyranoside | 211 | 11.6 | 18.2 | pH 7, 25 °C | Open record: β-galactosidase, 4-nitrophenyl alpha-L-arabinopyranoside |
| β-galactosidase | Escherichia coli | 4-nitrophenyl beta-D-fucopyranoside | 123.4 | 16.9 | 7.3 | pH 7, 25 °C | Open record: β-galactosidase, 4-nitrophenyl beta-D-fucopyranoside |
| β-galactosidase | Escherichia coli | 4-nitrophenyl beta-D-galactopyranoside | 90 | 0.041 | 2.2 × 10³ | pH 7, 25 °C | Open record: β-galactosidase, 4-nitrophenyl beta-D-galactopyranoside |
| β-galactosidasevariant H540E | Escherichia coli | 2-nitrophenyl beta-D-galactopyranoside1 mM Mg2+; continuous assay at 420 nm | 0.66 | 0.141 | 4.7 | pH 7, 25 °C | Open record: β-galactosidase variant H540E, 2-nitrophenyl beta-D-galactopyranoside |
| β-galactosidasevariant H540E | Escherichia coli | 2-nitrophenyl beta-D-galactopyranosideno Mg2+ (Mg2+ omitted, 10 mM EDTA) | 0.04 | 0.67 | 0.060 calc. | pH 7, 25 °C | Open record: β-galactosidase variant H540E, 2-nitrophenyl beta-D-galactopyranoside |
| β-galactosidasevariant H540E | Escherichia coli | 2-nitrophenyl beta-D-galactopyranoside1 mM Mg2+; acceptor present: Methanol (1 M) | 3.4 | — | — | pH 7, 25 °C | Open record: β-galactosidase variant H540E, 2-nitrophenyl beta-D-galactopyranoside |
| β-galactosidasevariant H540E | Escherichia coli | 2-nitrophenyl beta-D-galactopyranoside1 mM Mg2+; acceptor present: Glycerol (125 mM) | 3.1 | — | — | pH 7, 25 °C | Open record: β-galactosidase variant H540E, 2-nitrophenyl beta-D-galactopyranoside |
| β-galactosidasevariant H540E | Escherichia coli | 2-nitrophenyl beta-D-galactopyranoside1 mM Mg2+; acceptor present: L-Arabinose (250 mM) | 1.1 | — | — | pH 7, 25 °C | Open record: β-galactosidase variant H540E, 2-nitrophenyl beta-D-galactopyranoside |
| β-galactosidasevariant H540E | Escherichia coli | 2-nitrophenyl beta-D-galactopyranoside1 mM Mg2+; acceptor present: D-Galactose (250 mM) | 2.2 | — | — | pH 7, 25 °C | Open record: β-galactosidase variant H540E, 2-nitrophenyl beta-D-galactopyranoside |
| β-galactosidasevariant H540E | Escherichia coli | 2-nitrophenyl beta-D-galactopyranoside1 mM Mg2+; acceptor present: D-Fucose (250 mM) | 1.4 | — | — | pH 7, 25 °C | Open record: β-galactosidase variant H540E, 2-nitrophenyl beta-D-galactopyranoside |
| β-galactosidasevariant H540E | Escherichia coli | 2-nitrophenyl beta-D-galactopyranoside1 mM Mg2+; acceptor present: D-Talose (100 mM) | 0.7 | — | — | pH 7, 25 °C | Open record: β-galactosidase variant H540E, 2-nitrophenyl beta-D-galactopyranoside |
| β-galactosidasevariant H540E | Escherichia coli | 2-nitrophenyl beta-D-galactopyranoside1 mM Mg2+; acceptor present: 2-Deoxy-D-Galactose (150 mM) | 1.4 | — | — | pH 7, 25 °C | Open record: β-galactosidase variant H540E, 2-nitrophenyl beta-D-galactopyranoside |
| β-galactosidasevariant H540E | Escherichia coli | 2-nitrophenyl beta-D-galactopyranoside1 mM Mg2+; acceptor present: D-Glucose (300 mM) | 6 | — | — | pH 7, 25 °C | Open record: β-galactosidase variant H540E, 2-nitrophenyl beta-D-galactopyranoside |
| β-galactosidasevariant H540E | Escherichia coli | 4-nitrophenyl alpha-L-arabinopyranoside | 8.2 | 6 | 1.3 | pH 7, 25 °C | Open record: β-galactosidase variant H540E, 4-nitrophenyl alpha-L-arabinopyranoside |
| β-galactosidasevariant H540E | Escherichia coli | 4-nitrophenyl beta-D-fucopyranoside | 14.1 | 13.4 | 1 | pH 7, 25 °C | Open record: β-galactosidase variant H540E, 4-nitrophenyl beta-D-fucopyranoside |
| β-galactosidasevariant H540E | Escherichia coli | 4-nitrophenyl beta-D-galactopyranoside | 1.2 | 0.5 | 2.4 | pH 7, 25 °C | Open record: β-galactosidase variant H540E, 4-nitrophenyl beta-D-galactopyranoside |
| β-galactosidasevariant H540F | Escherichia coli | 2-nitrophenyl beta-D-galactopyranoside1 mM Mg2+; continuous assay at 420 nm | 0.1 | 0.11 | 0.91 | pH 7, 25 °C | Open record: β-galactosidase variant H540F, 2-nitrophenyl beta-D-galactopyranoside |
| β-galactosidasevariant H540F | Escherichia coli | 2-nitrophenyl beta-D-galactopyranosideno Mg2+ (Mg2+ omitted, 10 mM EDTA) | 0.02 | 1.91 | 0.010 calc. | pH 7, 25 °C | Open record: β-galactosidase variant H540F, 2-nitrophenyl beta-D-galactopyranoside |
| β-galactosidasevariant H540F | Escherichia coli | 2-nitrophenyl beta-D-galactopyranoside1 mM Mg2+; acceptor present: Methanol (1 M) | 0.2 | — | — | pH 7, 25 °C | Open record: β-galactosidase variant H540F, 2-nitrophenyl beta-D-galactopyranoside |
| β-galactosidasevariant H540F | Escherichia coli | 2-nitrophenyl beta-D-galactopyranoside1 mM Mg2+; acceptor present: Glycerol (125 mM) | 0.21 | — | — | pH 7, 25 °C | Open record: β-galactosidase variant H540F, 2-nitrophenyl beta-D-galactopyranoside |
| β-galactosidasevariant H540F | Escherichia coli | 2-nitrophenyl beta-D-galactopyranoside1 mM Mg2+; acceptor present: L-Arabinose (250 mM) | 0.09 | — | — | pH 7, 25 °C | Open record: β-galactosidase variant H540F, 2-nitrophenyl beta-D-galactopyranoside |
| β-galactosidasevariant H540F | Escherichia coli | 2-nitrophenyl beta-D-galactopyranoside1 mM Mg2+; acceptor present: D-Galactose (250 mM) | 0.16 | — | — | pH 7, 25 °C | Open record: β-galactosidase variant H540F, 2-nitrophenyl beta-D-galactopyranoside |
| β-galactosidasevariant H540F | Escherichia coli | 2-nitrophenyl beta-D-galactopyranoside1 mM Mg2+; acceptor present: D-Fucose (250 mM) | 0.12 | — | — | pH 7, 25 °C | Open record: β-galactosidase variant H540F, 2-nitrophenyl beta-D-galactopyranoside |
| β-galactosidasevariant H540F | Escherichia coli | 2-nitrophenyl beta-D-galactopyranoside1 mM Mg2+; acceptor present: D-Talose (100 mM) | 0.04 | — | — | pH 7, 25 °C | Open record: β-galactosidase variant H540F, 2-nitrophenyl beta-D-galactopyranoside |
| β-galactosidasevariant H540F | Escherichia coli | 2-nitrophenyl beta-D-galactopyranoside1 mM Mg2+; acceptor present: 2-Deoxy-D-Galactose (150 mM) | 0.16 | — | — | pH 7, 25 °C | Open record: β-galactosidase variant H540F, 2-nitrophenyl beta-D-galactopyranoside |
| β-galactosidasevariant H540F | Escherichia coli | 2-nitrophenyl beta-D-galactopyranoside1 mM Mg2+; acceptor present: D-Glucose (300 mM) | 0.44 | — | — | pH 7, 25 °C | Open record: β-galactosidase variant H540F, 2-nitrophenyl beta-D-galactopyranoside |
| β-galactosidasevariant H540F | Escherichia coli | 4-nitrophenyl alpha-L-arabinopyranoside | 11.9 | 0.57 | 20.9 | pH 7, 25 °C | Open record: β-galactosidase variant H540F, 4-nitrophenyl alpha-L-arabinopyranoside |
| β-galactosidasevariant H540F | Escherichia coli | 4-nitrophenyl beta-D-fucopyranoside | 8.5 | 2.9 | 2.9 | pH 7, 25 °C | Open record: β-galactosidase variant H540F, 4-nitrophenyl beta-D-fucopyranoside |
| β-galactosidasevariant H540F | Escherichia coli | 4-nitrophenyl beta-D-galactopyranoside | 0.1 | 0.45 | 0.22 | pH 7, 25 °C | Open record: β-galactosidase variant H540F, 4-nitrophenyl beta-D-galactopyranoside |
| β-galactosidasevariant H540N | Escherichia coli | 2-nitrophenyl beta-D-galactopyranoside1 mM Mg2+; continuous assay at 420 nm | 0.7 | 0.088 | 8 | pH 7, 25 °C | Open record: β-galactosidase variant H540N, 2-nitrophenyl beta-D-galactopyranoside |
| β-galactosidasevariant H540N | Escherichia coli | 2-nitrophenyl beta-D-galactopyranosideno Mg2+ (Mg2+ omitted, 10 mM EDTA) | 0.03 | 0.6 | 0.050 calc. | pH 7, 25 °C | Open record: β-galactosidase variant H540N, 2-nitrophenyl beta-D-galactopyranoside |
| β-galactosidasevariant H540N | Escherichia coli | 2-nitrophenyl beta-D-galactopyranoside1 mM Mg2+; acceptor present: Methanol (1 M) | 1.4 | — | — | pH 7, 25 °C | Open record: β-galactosidase variant H540N, 2-nitrophenyl beta-D-galactopyranoside |
| β-galactosidasevariant H540N | Escherichia coli | 2-nitrophenyl beta-D-galactopyranoside1 mM Mg2+; acceptor present: Glycerol (125 mM) | 1.89 | — | — | pH 7, 25 °C | Open record: β-galactosidase variant H540N, 2-nitrophenyl beta-D-galactopyranoside |
| β-galactosidasevariant H540N | Escherichia coli | 2-nitrophenyl beta-D-galactopyranoside1 mM Mg2+; acceptor present: L-Arabinose (250 mM) | 0.7 | — | — | pH 7, 25 °C | Open record: β-galactosidase variant H540N, 2-nitrophenyl beta-D-galactopyranoside |
| β-galactosidasevariant H540N | Escherichia coli | 2-nitrophenyl beta-D-galactopyranoside1 mM Mg2+; acceptor present: D-Galactose (250 mM) | 0.75 | — | — | pH 7, 25 °C | Open record: β-galactosidase variant H540N, 2-nitrophenyl beta-D-galactopyranoside |
| β-galactosidasevariant H540N | Escherichia coli | 2-nitrophenyl beta-D-galactopyranoside1 mM Mg2+; acceptor present: D-Fucose (250 mM) | 0.58 | — | — | pH 7, 25 °C | Open record: β-galactosidase variant H540N, 2-nitrophenyl beta-D-galactopyranoside |
| β-galactosidasevariant H540N | Escherichia coli | 2-nitrophenyl beta-D-galactopyranoside1 mM Mg2+; acceptor present: D-Talose (100 mM) | 0.56 | — | — | pH 7, 25 °C | Open record: β-galactosidase variant H540N, 2-nitrophenyl beta-D-galactopyranoside |
| β-galactosidasevariant H540N | Escherichia coli | 2-nitrophenyl beta-D-galactopyranoside1 mM Mg2+; acceptor present: 2-Deoxy-D-Galactose (150 mM) | 0.56 | — | — | pH 7, 25 °C | Open record: β-galactosidase variant H540N, 2-nitrophenyl beta-D-galactopyranoside |
| β-galactosidasevariant H540N | Escherichia coli | 2-nitrophenyl beta-D-galactopyranoside1 mM Mg2+; acceptor present: D-Glucose (300 mM) | 3.71 | — | — | pH 7, 25 °C | Open record: β-galactosidase variant H540N, 2-nitrophenyl beta-D-galactopyranoside |
| β-galactosidasevariant H540N | Escherichia coli | 4-nitrophenyl alpha-L-arabinopyranoside | 2 | 0.73 | 2.7 | pH 7, 25 °C | Open record: β-galactosidase variant H540N, 4-nitrophenyl alpha-L-arabinopyranoside |
| β-galactosidasevariant H540N | Escherichia coli | 4-nitrophenyl beta-D-fucopyranoside | 4.2 | 1.2 | 3.5 | pH 7, 25 °C | Open record: β-galactosidase variant H540N, 4-nitrophenyl beta-D-fucopyranoside |
| β-galactosidasevariant H540N | Escherichia coli | 4-nitrophenyl beta-D-galactopyranoside | 0.3 | 0.069 | 4.4 | pH 7, 25 °C | Open record: β-galactosidase variant H540N, 4-nitrophenyl beta-D-galactopyranoside |