Marks N J, Maule A G, Geary T G, Thompson D P, Li C, Halton D W, Shaw C
Comparative Neuroendocrinology Research Group, The Queen's University of Belfast, Belfast, BT9 7BL, Northern Ireland, United Kingdom.
Biochem Biophys Res Commun. 1998 Jul 20;248(2):422-5. doi: 10.1006/bbrc.1998.8982.
To date, seven FMRFamide-related peptides (FaRPs) have been structurally characterized from C. elegans, of which one is structurally identical to the parasitic nematode peptide AF2 (KHEYLRFamide). The other six FaRPs have so far been identified in free-living forms only. In the present study an additional FaRP was isolated and structurally characterized from an ethanolic extract of C. elegans. The extract was screened using a C-terminally directed FaRP antiserum, and the FMRFamide-immunoreactive peptide purified to homogeneity using HPLC. Approximately 80 pmol of the peptide was subjected to Edman degradation and the unequivocal primary structure of the K7-amide, KSAYMRFamide (PF3/AF8) was determined following a single gas-phase sequencing run. The molecular mass of the peptide was determined using a MALDI-TOF mass spectrometer and was found to be 919 (MH+), which is in agreement with the theoretical mass of C-terminally amidated PF3. A new flp-gene, designated flp-6, has recently been identified which encodes six copies of KSAYMRFamide (PF3/AF8).
迄今为止，已从秀丽隐杆线虫中鉴定出7种FMRF酰胺相关肽（FaRPs），其中一种在结构上与寄生线虫肽AF2（KHEYLRF酰胺）相同。另外6种FaRPs目前仅在自由生活形式中被鉴定出来。在本研究中，从秀丽隐杆线虫的乙醇提取物中分离出一种额外的FaRP并对其进行了结构表征。使用C末端导向的FaRP抗血清对提取物进行筛选，并通过高效液相色谱法将FMRF酰胺免疫反应性肽纯化至同质。对大约80 pmol的该肽进行了埃德曼降解，在单次气相测序后确定了K7酰胺KSAYMRF酰胺（PF3/AF8）明确的一级结构。使用基质辅助激光解吸电离飞行时间质谱仪测定该肽的分子量，发现为919（MH+），这与C末端酰胺化的PF3的理论质量一致。最近鉴定出一个新的flp基因，命名为flp-6，它编码6个拷贝的KSAYMRF酰胺（PF3/AF8）。
