NaCl对大麦幼苗根系蛋白质和游离氨基酸含量的影响

大麦幼苗在２００ｍｍｏｌ／ＬＮａＣｌ处理６ｄ过程中，根中蛋白水麦活性下降，可溶性蛋白含量在处理１、２、４ｄ下降，６ｄ时有所提高。多数游离氨基酸相对含量及其总量呈上升势，胁迫１、２、６ｄ时，总量较对照分别上升６４．２０％、５６．６９％和１．６９％，其中Ｐｒｏ、Ｇｌｕ、Ａｌａ和Ｔｈｒ较为突出，盐胁迫下根系质膜和液泡膜结合慢白含量上升。可溶性蛋经ＳＤＳ－ＰＡＧＥ电泳和扫描分析，在盐胁迫１、２、６ｄ中２５

EFFECTS OF NaCl ON PR0TEIN AND CONTENT OF FREE AMINO ACIDS IN ROOTS OF BARLEY

Under 200 mmol/L NaCl for 6 days,the activity of proteolytic enzymes in the rootof barley seedlings decreased. The content of soluble protein decreased during the former4 days,but sllghtly increased on the 6th day. On the 1st, 2nd and 6th day,the amounts oftotal free amino acids increased 64. 20%, 56. 69 % and 71. 69 %, respectively. Among the17 kinds of amino acids measured .the contents of Pro,Glu,Ala and Thr increased obviously, especially on the 1st and 2nd day. The contents of membrane-bound proteln inplasma membrane and tonoplast from the root of salt-stressed barley were both increased. The analysis of soluble protein by SDS-PAGE and thin layer scanning showedthat the synthesis of 25. 22 kD polypeptide was enhanced during the whole stress process,and that of 44. 68 kD polypeptide was enhanced only on the 2nd and 6th day.