Invertebrate peptides

The invertebrate peptides PCH (pigment-concentrating hormone 46) and AKH I (adipokinetic hormone 47) were the first neuropeptides from invertebrates to have their structure and synthesis described by L. Josefsson in 1983 94). 

Additional myotropic/inhibitory neuropeptide structures will be characterized on the basis of immunological similarity to vertebrate and invertebrate peptide structures, and also with the techniques of molecular biology. Two initial successes with those methods are discussed in this report (17,25). In addition, antibodies raised against FMRFamide were used to isolate and structurally characterize a nonapeptide containing C-terminal FMRFamide from head extracts of Drosophila (26). Subsequently, the gene that codes for this nonapeptide and eight other FMRFamide-related structures was isolated and sequenced (27,28). 

Some Microbial and Invertebrate Peptide Hormones Some Proteins Important to the Formation and Functioning of Synaptic... 

Several peptides are related in different ways to these classical opioid peptides. FMREamide (Phe-Met-Arg-Phe-NH2) contains the first four amino acids of enkephalin and is active in various invertebrates (58) FMREamide-related peptides also have been located in the mammalian brain. Although these... 

A considerable number of mycotoxins that show high toxicity to vertebrates and/ or invertebrates are produced by organisms associated with crop plants (Flannigan 1991). There are many known cases of human poisoning caused by such compounds. There are three broad categories of mycotoxins represented here, based on the structures of the intermediates from which these secondary metabolites are derived. They are (1) compounds derived from polyketides, (2) terpenes derived from mevalonic acid, and (3) cyclic peptides and derivatives thereof. 

Maule, A.G., Geary T.G., Bowman, J.W., Marks, N.J., Blair, K.L., Halton, D.W., Shaw, C. and Thompson, D.P. (1995b) Inhibitory effects of nematode FMRFamide-related peptides (FaRPs) on muscle-strips from Ascaris suum. Invertebrate Neuroscience 1, 255-265. 

The literature contains numerous references to the use of MS/MS in the determination of new neuropeptides in identified cells of invertebrates (Bulau et al., 2004, for a recent example) and this technique is now being applied to in situ analysis of vertebrate tissues (Fournier et al., 2003). MS/MS is also used for studies of neuropeptide processing (Nilsson et al., 2001), pharmacokinetics of synthetic peptides (Mock et al., 2002), nonpeptide drug metabolism (Kamel et al., 2003), identification of peptides purified by immunoaffinity (Suresh Babu et al., 2004), and MALDI/MS/MS techniques adaptable to brain dialysis (Bogan and Agnes, 2004). 

Characterization of Bioactive Peptides Obtained from Marine Invertebrates... 

Bioactive peptides as products of hydrolysis of diverse marine invertebrate (shellfish, crustacean, rotifer, etc.) proteins are the focus of current research. After much research on these muscles and byproducts, some biologically active peptides were identified and applied to useful compounds for human utilization. This chapter reviews bioactive peptides from marine invertebrates in regarding to their bioactivities. Additionally, specific characteristics of antihypertensive, anti-Alzheimer, antioxidant, antimicrobial peptide enzymatic production, methods to evaluate bioactivity capacity, bioavailability, and safety concerns of peptides are reviewed. 

As ACE-inhibiting peptides have already been mentioned with regard to various vertebrate muscles, and as the structure of vertebrate and invertebrate muscle is very similar, invertebrates may be new sources of ACE-inhibiting peptides. However, while many ACE-inhibitor peptides have been derived from vertebrate muscle, very few studies on the subject have been conducted. 

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