ω-transaminases are able to catalyze the reversible transfer of amino groups between diverse amino compounds (such as amino acids, alkyl amines, aromatic amines) and carbonyl compounds (such as aldehydes, ketones, ketoacids). ω-transaminases exhibit great application prospects in the field of chiral amine biosynthesis because of their desirable properties, such as wide range of substrates, high stereoselectivity, and mild catalytic conditions. It is therefore important for China to develop efficient, specific, and environment-friendly chiral amine production technologies with independent intellectual property rights, which is of great significance for the development of pharmaceutical, pesticide, and material industries. This review systematically summarizes the Chinese patents regarding ω-transaminase filed by Chinese institutions in the recent decade. The development of ω-transaminase resource, enzymatic property improvement by protein engineering, application in chiral amine synthesis, and development of production technologies are elaborated. This review will shed light on further basic and application studies of ω-transaminase.
Transaminases/genetics* ; Amino Acids ; China ; Aldehydes ; Amines

Objective: To explore the characteristics of plasma Epstein-Barr virus (EBV) DNA in primary infection in pediatric cases. Methods: The laboratory and clinical data of 571 children diagnosed with EBV primary infection in Children's Hospital of Fudan University during September 1^st, 2017 to September 30^th, 2018 were retrospectively analyzed. According to the results of plasma EBV DNA, they were divided into positive group and negative group. According to the EBV DNA, they were devided into high plasma virol load group and low plasma virol load group. The Chi-square test, Wilcoxon rank sum test were used to compare the differences between groups. Results: Among the 571 children with EBV primary infection, 334 were males and 237 were females. The age of first diagnosis was 3.8 (2.2, 5.7) years. There were 255 cases in positive group and 316 cases in negative group. The percentage of cases with fever,hepatomegaly and (or) splenomegaly, elevated transaminase in the positive group were higher than those in the negative group (235 cases (92.2%) vs. 255 cases (80.7%), χ²=15.22, P<0.001; 169 cases (66.3%) vs. 85 cases (26.9%), χ²=96.80, P<0.001; and 144 cases (56.5%) vs. 120 cases (38.0%), χ²=18.27, P<0.001; respectively).In the positive group, 70 cases were followed up for 46 (27, 106) days, 68 cases (97.1%) turned negative within 28 days, with the exception of 2 cases (2.9%) developed chronic active EBV infection by follow-up revision.There were 218 cases in high plasma viral DNA copies group and 37 cases in low copies group. More cases presented with elevated transaminases in the high plasma viral DNA copies group than those in the low group (75.7% (28/37) vs. 56.0%(116/207), χ²=5.00, P=0.025).Both the positive rate of EBV DNA in peripheral blood leukocytes (84.2% (266/316) vs. 44.7% (255/571), χ²=76.26, P<0.001) and the copies of EBV DNA (7.0×10⁷ (1.3×10⁷, 3.0×10⁸) vs. 3.1×10⁶ (1.6×10⁶, 6.1×10⁶) copies /L, Z=15.23, P<0.001) were higher than that of plasma. Conclusions: In immunocompetent pediatric cases diagnosed as EBV primary infection, cases with positive plasma EBV DNA were prone to have fever, hepatomegaly and (or) splenomegaly, and elevated transaminase than those with negative plasma viral DNA. The plasma EBV DNA usually turns negative within 28 days after initial diagnosis.Most cases with high viral load in plasma showed elevated aminotransferase.
Female ; Male ; Humans ; Child ; DNA, Viral ; Herpesvirus 4, Human ; Epstein-Barr Virus Infections ; Hepatomegaly ; Retrospective Studies ; Splenomegaly ; Fever ; Transaminases

ω-transaminase (ω-TA) is a natural biocatalyst that has good application potential in the synthesis of chiral amines. However, the poor stability and low activity of ω-TA in the process of catalyzing unnatural substrates greatly hampers its application. To overcome these shortcomings, the thermostability of (R)-ω-TA (AtTA) from Aspergillus terreus was engineered by combining molecular dynamics simulation assisted computer-aided design with random and combinatorial mutation. An optimal mutant AtTA-E104D/A246V/R266Q (M3) with synchronously enhanced thermostability and activity was obtained. Compared with the wild- type (WT) enzyme, the half-life t_1/2 (35 ℃) of M3 was prolonged by 4.8-time (from 17.8 min to 102.7 min), and the half deactivation temperature (T¹⁰₅₀) was increased from 38.1 ℃ to 40.3 ℃. The catalytic efficiencies toward pyruvate and 1-(R)-phenylethylamine of M3 were 1.59- and 1.56-fold that of WT. Molecular dynamics simulation and molecular docking showed that the reinforced stability of α-helix caused by the increase of hydrogen bond and hydrophobic interaction in molecules was the main reason for the improvement of enzyme thermostability. The enhanced hydrogen bond of substrate with surrounding amino acid residues and the enlarged substrate binding pocket contributed to the increased catalytic efficiency of M3. Substrate spectrum analysis revealed that the catalytic performance of M3 on 11 aromatic ketones were higher than that of WT, which further showed the application potential of M3 in the synthesis of chiral amines.
Transaminases/chemistry* ; Molecular Docking Simulation ; Amines/chemistry* ; Pyruvic Acid/metabolism* ; Enzyme Stability

OBJECTIVES: To explore the value of the combined use of aspartate aminotransferase-to-platelet ratio index (APRI) and total bile acid (TBA) for predicting parenteral nutrition-associated cholestasis (PNAC) in preterm infants with gestational age <34 weeks. METHODS: A retrospective analysis was performed on medical data of 270 preterm infants born at <34 weeks of gestation who received parenteral nutrition (PN) during hospitalization in the First Affiliated Hospital of Wannan Medical College from January 2019 to September 2022, including 128 infants with PNAC and 142 infants without PNAC. The medical data between the two groups were compared, and predictive factors for the development of PNAC were explored through multivariate logistic regression analysis. The receiver operating characteristic (ROC) curve was used to evaluate the value of APRI alone, TBA alone, and the combination of both for predicting PNAC. RESULTS: TBA levels in the PNAC group after 1, 2, and 3 weeks of PN were higher than those in the non-PNAC group (P<0.05). APRI in the PNAC group after 2 and 3 weeks of PN was higher than that in the non-PNAC group (P<0.05). Multivariate logistic regression analysis showed that elevated APRI and TBA after 2 weeks of PN were predictive factors for PNAC in preterm infants (P<0.05). ROC curve analysis showed that the sensitivity, specificity, and area under the curve (AUC) for predicting PNAC by combining APRI and TBA after 2 weeks of PN were 0.703, 0.803, and 0.806, respectively. The AUC for predicting PNAC by combining APRI and TBA was higher than that of APRI or TBA alone (P<0.05). CONCLUSIONS After 2 weeks of PN, the value of combining APRI and TBA for predicting PNAC is high in preterm infants with gestational age <34 weeks.
Infant, Newborn ; Infant ; Humans ; Gestational Age ; Infant, Premature ; Retrospective Studies ; Bile Acids and Salts ; Parenteral Nutrition ; Transaminases

OBJECTIVE: To explore the clinical features and genetic etiology of a child with glycogen storage disease VI (GSD-VI). METHODS: Clinical data and laboratory results of the patient were collected. Whole exome sequencing (WES) was carried out for the patient. Candidate variant and its parental origin was verified by Sanger sequencing. RESULTS: The patient was a 3-year-and-9-month old boy whom has featured abdominal distention, hepatomegaly, short stature and elevated hepatic transaminase. WES revealed the he has harbored compound heterozygous variants of the PYGL gene, namely c.697G>A (p.Gly233Ser) and c.320dupA (p.Asn107fs). Sanger sequencing has verified that the two variants have derived from his father and mother, respectively. The c.320dupA (p.Asn107fs) variant was unreported previously. CONCLUSION The compound heterozygous variants of the PYGL gene probably underlay the GSD-VI in this patient. Above finding has enriched the spectrum of PYGL gene variants and provided a basis for the treatment and genetic counseling.
Child ; Genetic Testing ; Glycogen Storage Disease Type VI/genetics* ; Humans ; Infant ; Male ; Mutation ; Transaminases/genetics* ; Exome Sequencing

OBJECTIVE: To evaluate the effect and safety of low-dose of apatinib and S-1 combined with Jianpi Bushen Jiedu Decoction (JBJD) in patients with metastatic colorectal cancer (mCRC) who have failed second or above lines treatment, in order to provide more treatment option for mCRC patients by integrated medicine. METHODS: Thirteen patients were selected from a single-arm, open-label clinical study from April 2019 to September 2020. The patients were treated with low-dose apatinib (250 mg, once a day) and S-1 (20 mg, twice a day) combined with JBJD for at least one cycle and were followed up to August 2021. The primary endpoint was disease progression-free survival (PFS). Disease control rate (DCR), objective response rate (ORR), and overall survival (OS) of patients were observed as the secondary endpoints. Adverse events were recorded as well. RESULTS: The average age of the 13 patients was 56.5 ±13.0 years and 76.9% were male. The median PFS and median OS were 4.6 and 8.3 months, respectively. The ORR was 7.7% (1/13) while the DCR was 61.5% (8/13). The common adverse events were hypertension, proteinuria, elevated transaminase, and thrombocytopenia. One patient experienced thrombocytopenia of grade 3. CONCLUSIONS Patients with mCRC after failure of the second or above lines of treatment may potentially benefit from the treatment of low-dose apatinib and S-1 combined with JBJD because of its similar effect as the standard dose of target therapy and relatively better safety. (Registration No. ChiCTR1900022673).
Adult ; Aged ; Antineoplastic Agents/therapeutic use* ; Colonic Neoplasms ; Female ; Humans ; Male ; Middle Aged ; Pyridines ; Thrombocytopenia/drug therapy* ; Transaminases/therapeutic use*

OBJECTIVE: To investigate the influence of GPT2（glutamic pyruvate transaminase 2）to biological characteristics of human acute myeloid leukemia cell line HL-60. METHODS: The expression of GPT2 in hematological tumor and AML cell was detected. The lentvirus-mediated of short-hairpin RNA (shRNA) was constricted, and the knock-down efficiency of HL-60 in AML cell after infected by lentvirus-mediated was detected by Western blot and Q-PCR. CCK-8 assay and soft agar colony formation assay were used to detect the effect of GPT2 gene deletion to the cell proliferation potential. Fluorescence activated cell sorting(FACS) was used to analyze the effect of gene deletion to the cell cycle and Caspase 3/7 Activity Assay Kit was used to analyze the effect of GPT2 gene deletion to the cell apoptosis. RESULTS: GPT2 showed mRNA high expression in AML patients. CCK-8, soft agar assay, and Caspase 3/7 Activity Assay Kit results showed that compared with shCtrl group, the cells in shGPT2-1、shGPT2-2、shGPT2-3 group showed the slowing down on proliferation, decreasing on colony ability, and the apoptosis of the cells was increasing significantly. FACS showed that GPT2 gene was related to the cycle of HL-60 cell. CONCLUSION GPT2 appears to involve the proliferation, cycle distribution and apoptosis of AML cell HL-60. The deletion of GPT gene can lead to the inhibitation of cells proliferation and increase apoptosis.
Apoptosis ; Cell Proliferation ; HL-60 Cells ; Humans ; Leukemia, Myeloid, Acute ; Pyruvates ; Transaminases

BACKGROUND/AIMS: Noninvasive markers of liver fibrosis in alcoholic liver disease (ALD) are crucial to establish early intervention. Previous studies have suggested that plasma levels of cleaved keratin-18 (K18; M30) fragments can predict the severity of liver disease. The aim of this study was to correlate plasma M30 levels with stages of liver fibrosis in ALD. METHODS: Patients with ALD (n=139, 79.1% males) and liver histology were included, and plasma samples were collected to quantify plasma M30 levels. Patients were stratified into five groups by fibrosis stage (F0=14; F1=15; F2=35; F3=17; and F4=58) according to the Kleiner score. Differences between groups were evaluated using the chi-square test or analysis of variance. Trends by fibrosis stage were calculated by logistic regression analysis, and sensitivity, specificity and positive and negative predictive values were determined. RESULTS: There were no significant differences in M30 levels among fibrosis stages. The correlation between plasma M30 levels and fibrosis was poor (Pearson’s correlation coefficient=0.13, Spearman rho=0.20 [p=0.02]), and M30 levels did not correlate with alcohol-specific histological features. However, significant correlations of M30 levels with aspartate aminotransferase (Spearman rho=0.653, p < 0.001) and alanine aminotransferase (Spearman rho=0.432, p < 0.001) were found. M30 levels of >200 U/L reveal a sensitivity for predicting cirrhosis of 84.5% with a negative predictive value of 73.5%. CONCLUSIONS: Plasma M30 levels are often elevated in ALD and correlate with serum transaminases but do not reflect fibrosis. The usefulness as a prognostic marker awaits evaluation in prospective studies.
Alanine Transaminase ; Alcoholics* ; Apoptosis ; Aspartate Aminotransferases ; Caspases ; Early Intervention (Education) ; Fibrosis ; Humans ; Keratin-18 ; Liver Cirrhosis* ; Liver Diseases ; Liver Diseases, Alcoholic ; Liver* ; Logistic Models ; Plasma* ; Prospective Studies ; Sensitivity and Specificity ; Transaminases

No abstract available.
Liver ; Norovirus ; Transaminases

As a new beer fermentation technology, high temperature and high gravity fermentation has brought many benefits to brewery industry, but there are also a series of problems such as the decrease of yeast flocculation ability at the end of fermentation and the high concentration of higher alcohols. To increase yeast flocculation ability and reduce the production of higher alcohols in high temperature and high gravity fermentation of beer, BAT2 was replaced by the FLO5 expression cassette to obtain the mutant strain S6-BF2. Real-time quantitative PCR showed that the relative transcriptional level of FLO5 in S6-BF2 improved 17.8 times compared with that in S6. The flocculation ability of mutant S6-BF2 heightened by 63% compared to that of the original strain S6, and the concentration of higher alcohols decreased from 175.58 mg/L to 159.58 mg/L in high temperature and high gravity fermentation of beer. Moreover, the activity of mitochondrial branched-chain amino acid transferase was repressed, resulting in the production of higher alcohols of 142.13 mg/L, reduced by 18.4% compared to that of the original strain S6, meanwhile, the flocculation ability of mutant S6-BF2B1 kept unchanged compared to the mutant S6-BF2. The determination result of flavor compounds showed that the higher alcohols/ester ratio in beer was reasonable. This research has suggested an effective strategy for enhancing yeast flocculation ability and decreasing production of higher alcohols in high-temperature and high-gravity brewing.
Beer ; Fermentation ; Hypergravity ; Saccharomyces cerevisiae ; Saccharomyces cerevisiae Proteins ; Temperature ; Transaminases