| Tsai YH, Lai WFT, Chen SH and Johnson RL. |
------>authors3_c=None ------>paper_class1=1 ------>Impact_Factor=None ------>paper_class3=2 ------>paper_class2=1 ------>vol=244 ------>confirm_bywho=cmbdshih ------>insert_bywho=??? ------>Jurnal_Rank=None ------>authors4_c=None ------>comm_author=1 ------>patent_EDate=None ------>authors5_c=None ------>publish_day=None ------>paper_class2Letter=None ------>page2=166 ------>medlineContent= ------>unit=E0600 ------>insert_date=19991209 ------>iam=1 ------>update_date= ------>author=??? ------>change_event=5 ------>ISSN=None ------>authors_c=None ------>score=-15 ------>journal_name=Biochem. Biophys Research Common ------>paper_name=A novel calcium-dependent enzyme capable of incorporation putrescine into protein. ------>confirm_date=20010330 ------>tch_id=083002 ------>pmid=9762920 ------>page1=161 ------>fullAbstract=Tissue-transglutaminase (t-TGase) is a family of calcium-dependent enzymes. A Ca2+-independent soluble enzyme, in addition to t-TGase, capable of incorporating polyamines into proteins was demonstrated in rat intestinal mucosa. The Ca2+-independent enzyme was stimulated 2- to 5-fold by Fe2+ and Co2+ ions but inhibited by Cu2+ and Zn2+ ions. The Ca2+-stimulated t-TGase activity was inhibited by divalent ions in the following order: Zn2+, Fe2+ >Co2+ > Cu2+. The opposite effects of EGTA, Fe2+ and Co2+ on these two enzyme activities indicate that they are two distinct classes of enzymes. Competition studies demonstrated differential preferences of the two enzymes for substrates. The Ca2+-dependent enzyme preferred putrescine, monodansylcadaverine > cadaverine, spermidine, spermine > 1,10-diaminodecane > triethylbutylamine. On the other hand, the Ca2+-independent enzyme preferred putrescine > cadaverine > spermine, I,10-diaminodecane > spermidine > monodansylcadaverine > triethylbutylamine. Further studies with divalent ions excluded the possible association of this novel Ca2+-independent enzyme with diamine oxidase. Finally, the Ca2+-independent enzyme had a higher affinity for putrescine (Km = 0.02 mM) than did Ca2+-dependent t-TGase (0.2 mM). As judged by gel filtration on HiPrep Sephacryl 200 column, the Ca2+-independent enzyme had a molecular weight of approximately 48 kDa, the intestinal Ca2+-dependent t-TGase was about 188 kDa while that of testicular t-TGase was about 96 kDa. In conclusion, the Ca2+-independent enzyme is stimulated by cobalt or ferric ions, and selectively incorporates aliphatic diamines or polyamines with symmetric amino groups. The observed Ca2+-independent enzyme activity is not related to diamine oxidase or its products. With a 10 times greater affinity for putrescine, the calcium-independent, 48-kDa intestinal enzyme may mediate polyamine function better than calcium dependent, 188-kDa intestinal tissue transglutaminase in the intestinal mucosa. ------>tmu_sno=None ------>sno=850 ------>authors2=None ------>authors3=None ------>authors4=None ------>authors5=None ------>authors6=None ------>authors6_c=None ------>authors=Tsai YH, Lai WFT, Chen SH and Johnson RL. ------>delete_flag=0 ------>SCI_JNo=None ------>authors2_c=None ------>publish_area=None ------>updateTitle=Two distinct classes of rat intestinal mucosal enzymes incorporating putrescine into protein. ------>language=2 ------>check_flag=0 ------>submit_date= ------>country=None ------>no= ------>patent_SDate=None ------>update_bywho= ------>publish_year=1998 ------>submit_flag= ------>publish_month=None |