GPT, also known as alanine aminotransferases (ALT1), catalyzes the reversible transamination between alanine and 2-oxoglutarate to form pyruvate and glutamate. This protein plays a key role in the intermediary metabolism of glucose and amino acids. It is widely used as an index of liver integrity or hepatocellular damage in clinical settings. Source: Recombinant protein corresponding to aa1-496 from human GPT, fused to His-tag at N-terminal expressed in E. coli. Molecular Weight: ~56.8kD (516aa) Specific Activity: >100units/mg, and is defined as the amount of enzyme that cleaves 1umole of L-Alanine to L-Glutamate/minute at pH 7.5 at 37C. Activity Assay: 1. Prepare a 180ul assay buffer into a suitable container: The concentrations are 100mM Tris-HCl, 111mM L-Alanine, 0.4mM b-NADH, 6.4mM a-Oxoglutarate, 2.3units/ml LDHA. 2. Equilibrate to 37C and monitor at A340nm until the value is constant using a spectrophotometer. 3. Add 20ul of recombinant GPT protein 5ug/ml in assay buffer. 4. Record the decrease in A340nm for 5 minutes. Amino Acid Sequence: MGSSHHHHHH SSGLVPRGSH MASSTGDRSQ AVRHGLRAKV LTLDGMNPRV RRVEYAVRGP IVQRALELEQ ELRQGVKKPF TEVIRANIGD AQAMGQRPIT FLRQVLALCV NPDLLSSPNF PDDAKKRAER ILQACGGHSL GAYSVSSGIQ LIREDVARYI ERRDGGIPAD PNNVFLSTGA SDAIVTVLKL LVAGEGHTRT GVLIPIPQYP LYSATLAELG AVQVDYYLDE ERAWALDVAE LHRALGQARD HCRPRALCVI NPGNPTGQVQ TRECIEAVIR FAFEERLFLL ADEVYQDNVY AAGSQFHSFK KVLMEMGPPY AGQQELASFH STSKGYMGEC GFRGGYVEVV NMDAAVQQQM LKLMSVRLCP PVPGQALLDL VVSPPAPTDP SFAQFQAEKQ AVLAELAAKA KLTEQVFNEA PGISCNPVQG AMYSFPRVQL PPRAVERAQE LGLAPDMFFC LRLLEETGIC VVPGSGFGQR EGTYHFRMTI LPPLEKLRLL LEKLSRFHAK FTLEYS Storage and Stability: May be stored at 4C for short-term only. Aliquot to avoid repeated freezing and thawing.. Store at -20C. Aliquots are stable for 6 months after receipt at -20C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.
