{"title":"B-016 用重组人载脂蛋白酶对磷酸吡多胺(PAMP)进行 AST/ALT 试剂评估","authors":"T Oba, M Miyachi, Y Taketani, M Mizuguchi","doi":"10.1093/clinchem/hvae106.380","DOIUrl":null,"url":null,"abstract":"Background ApoAST/ALT, which have lost a coenzyme such as pyridoxal phosphate (PALP), are normally present at low levels in serum. To form the holoenzyme, IFCC recommends adding PALP into AST/ALT reagents. However, commercial reagents often do not use PALP due to its instability. In recent years, pyridoxamine phosphate (PAMP), a more stable coenzyme, has been marketed. However, the differences in holo formation ability and reagent stability between their coenzymes are not well understood. In this study, we focused on the preparation of PAMP and recombinant human ApoAST/ALT (rhApoAST/ALT), followed by fundamental investigations into their use as AST/ALT reagents. Methods PAMP was synthesized from pyridoxamine through an enzymatic reaction using pyridoxal kinase. The reaction product was purified to achieve a purity of >99% in HPLC. rhApoAST/ALT were expressed in Escherichia coli and purified with chromatography. AST/ALT assay was performed on a Hitachi 7180 automatic analyzer. PALP reagents for AST/ALT were designed to correspond with the final concentration of the IFCC method. PAMP reagents were prepared with PAMP instead of PALP. To evaluate the holo formation ability of PALP and PAMP reagents, we measured a dilution series of rhApoAST/ALT. To assess stability, the reagents were stored at 11°C for 3 months and then measured same. The reagents were subjected to content analysis by HPLC. Results Similar results were shown between coenzymes in the evaluation of holo formation ability, and high correlations were observed. As for the stability test, the values of PALP reagents decreased after 3 months, while the values of PAMP reagents did not. Content analysis showed that a spontaneous transamination occurred in PALP reagents. These results were observed at both AST and ALT reagents. Conclusions In AST/ALT reagents, both PAMP and PALP can activate apoenzymes. While PAMP is stable, PALP causes a decrease in reagent performance due to a spontaneous transamination.","PeriodicalId":10690,"journal":{"name":"Clinical chemistry","volume":null,"pages":null},"PeriodicalIF":7.1000,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"B-016 Evaluation of pyridoxamine phosphate (PAMP) for AST/ALT reagents with recombinant human apoenzymes\",\"authors\":\"T Oba, M Miyachi, Y Taketani, M Mizuguchi\",\"doi\":\"10.1093/clinchem/hvae106.380\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Background ApoAST/ALT, which have lost a coenzyme such as pyridoxal phosphate (PALP), are normally present at low levels in serum. To form the holoenzyme, IFCC recommends adding PALP into AST/ALT reagents. However, commercial reagents often do not use PALP due to its instability. In recent years, pyridoxamine phosphate (PAMP), a more stable coenzyme, has been marketed. However, the differences in holo formation ability and reagent stability between their coenzymes are not well understood. In this study, we focused on the preparation of PAMP and recombinant human ApoAST/ALT (rhApoAST/ALT), followed by fundamental investigations into their use as AST/ALT reagents. Methods PAMP was synthesized from pyridoxamine through an enzymatic reaction using pyridoxal kinase. The reaction product was purified to achieve a purity of >99% in HPLC. rhApoAST/ALT were expressed in Escherichia coli and purified with chromatography. AST/ALT assay was performed on a Hitachi 7180 automatic analyzer. PALP reagents for AST/ALT were designed to correspond with the final concentration of the IFCC method. PAMP reagents were prepared with PAMP instead of PALP. To evaluate the holo formation ability of PALP and PAMP reagents, we measured a dilution series of rhApoAST/ALT. To assess stability, the reagents were stored at 11°C for 3 months and then measured same. The reagents were subjected to content analysis by HPLC. Results Similar results were shown between coenzymes in the evaluation of holo formation ability, and high correlations were observed. As for the stability test, the values of PALP reagents decreased after 3 months, while the values of PAMP reagents did not. Content analysis showed that a spontaneous transamination occurred in PALP reagents. These results were observed at both AST and ALT reagents. Conclusions In AST/ALT reagents, both PAMP and PALP can activate apoenzymes. While PAMP is stable, PALP causes a decrease in reagent performance due to a spontaneous transamination.\",\"PeriodicalId\":10690,\"journal\":{\"name\":\"Clinical chemistry\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":7.1000,\"publicationDate\":\"2024-10-02\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Clinical chemistry\",\"FirstCategoryId\":\"3\",\"ListUrlMain\":\"https://doi.org/10.1093/clinchem/hvae106.380\",\"RegionNum\":2,\"RegionCategory\":\"医学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"MEDICAL LABORATORY TECHNOLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Clinical chemistry","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1093/clinchem/hvae106.380","RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MEDICAL LABORATORY TECHNOLOGY","Score":null,"Total":0}
B-016 Evaluation of pyridoxamine phosphate (PAMP) for AST/ALT reagents with recombinant human apoenzymes
Background ApoAST/ALT, which have lost a coenzyme such as pyridoxal phosphate (PALP), are normally present at low levels in serum. To form the holoenzyme, IFCC recommends adding PALP into AST/ALT reagents. However, commercial reagents often do not use PALP due to its instability. In recent years, pyridoxamine phosphate (PAMP), a more stable coenzyme, has been marketed. However, the differences in holo formation ability and reagent stability between their coenzymes are not well understood. In this study, we focused on the preparation of PAMP and recombinant human ApoAST/ALT (rhApoAST/ALT), followed by fundamental investigations into their use as AST/ALT reagents. Methods PAMP was synthesized from pyridoxamine through an enzymatic reaction using pyridoxal kinase. The reaction product was purified to achieve a purity of >99% in HPLC. rhApoAST/ALT were expressed in Escherichia coli and purified with chromatography. AST/ALT assay was performed on a Hitachi 7180 automatic analyzer. PALP reagents for AST/ALT were designed to correspond with the final concentration of the IFCC method. PAMP reagents were prepared with PAMP instead of PALP. To evaluate the holo formation ability of PALP and PAMP reagents, we measured a dilution series of rhApoAST/ALT. To assess stability, the reagents were stored at 11°C for 3 months and then measured same. The reagents were subjected to content analysis by HPLC. Results Similar results were shown between coenzymes in the evaluation of holo formation ability, and high correlations were observed. As for the stability test, the values of PALP reagents decreased after 3 months, while the values of PAMP reagents did not. Content analysis showed that a spontaneous transamination occurred in PALP reagents. These results were observed at both AST and ALT reagents. Conclusions In AST/ALT reagents, both PAMP and PALP can activate apoenzymes. While PAMP is stable, PALP causes a decrease in reagent performance due to a spontaneous transamination.
期刊介绍:
Clinical Chemistry is a peer-reviewed scientific journal that is the premier publication for the science and practice of clinical laboratory medicine. It was established in 1955 and is associated with the Association for Diagnostics & Laboratory Medicine (ADLM).
The journal focuses on laboratory diagnosis and management of patients, and has expanded to include other clinical laboratory disciplines such as genomics, hematology, microbiology, and toxicology. It also publishes articles relevant to clinical specialties including cardiology, endocrinology, gastroenterology, genetics, immunology, infectious diseases, maternal-fetal medicine, neurology, nutrition, oncology, and pediatrics.
In addition to original research, editorials, and reviews, Clinical Chemistry features recurring sections such as clinical case studies, perspectives, podcasts, and Q&A articles. It has the highest impact factor among journals of clinical chemistry, laboratory medicine, pathology, analytical chemistry, transfusion medicine, and clinical microbiology.
The journal is indexed in databases such as MEDLINE and Web of Science.