如何用正则表达式匹配文本中的中的氨基酸序列？

文本是
REMARK 900 RELATED ID: 1IEU RELATED DB: PDB
DBREF 1IET A -3 94 UNP P00173 CYB5_RAT 1 98
SEQRES 1 A 98 ALA GLU GLN SER ASP LYS ASP VAL LYS TYR TYR THR LEU
SEQRES 2 A 98 GLU GLU ILE GLN LYS HIS LYS ASP SER LYS SER THR TRP
SEQRES 3 A 98 VAL ILE LEU HIS HIS LYS VAL TYR ASP LEU THR LYS PHE
SEQRES 4 A 98 LEU GLU GLU HIS PRO GLY GLY GLU GLU VAL LEU ARG GLU
SEQRES 5 A 98 GLN ALA GLY GLY ASP ALA THR GLU ASN PHE GLU ASP VAL
SEQRES 6 A 98 GLY HIS SER THR ASP ALA ARG GLU LEU SER LYS THR TYR
SEQRES 7 A 98 ILE ILE GLY GLU LEU HIS PRO ASP ASP ARG SER LYS ILE
SEQRES 8 A 98 ALA LYS PRO SER GLU THR LEU
要求：
1：用正则表达式找到 如 'ALA GLU GLN SER ASP LYS ASP VAL LYS TYR TYR THR LEU '三个字母为序的list
2：同时能够定位到 ‘SEQRES’ 的行

import re

a = '''REMARK 900 RELATED ID: 1IEU RELATED DB: PDB
DBREF 1IET A -3 94 UNP P00173 CYB5_RAT 1 98
SEQRES 1 A 98 ALA GLU GLN SER ASP LYS ASP VAL LYS TYR TYR THR LEU
SEQRES 2 A 98 GLU GLU ILE GLN LYS HIS LYS ASP SER LYS SER THR TRP
SEQRES 3 A 98 VAL ILE LEU HIS HIS LYS VAL TYR ASP LEU THR LYS PHE
SEQRES 4 A 98 LEU GLU GLU HIS PRO GLY GLY GLU GLU VAL LEU ARG GLU
SEQRES 5 A 98 GLN ALA GLY GLY ASP ALA THR GLU ASN PHE GLU ASP VAL
SEQRES 6 A 98 GLY HIS SER THR ASP ALA ARG GLU LEU SER LYS THR TYR
SEQRES 7 A 98 ILE ILE GLY GLU LEU HIS PRO ASP ASP ARG SER LYS ILE
SEQRES 8 A 98 ALA LYS PRO SER GLU THR LEU'''

b = re.findall(r'((?<=\n)SEQRES.*?)((?: [A-Z]{3})+)',a)
for i in b:
    print(i[0])
    print(i[1].strip())
    

你是要这样？

你原文是什么，要找的文本规则是什么