What is the chemical structure and amino-acid sequence of gelatide?
Executive summary
“Gelatide” does not appear in the provided reporting; available sources discuss gelatin — a heterogeneous mixture of polypeptides produced by partial hydrolysis of collagen, rich in glycine, proline and hydroxyproline and lacking a single defined primary sequence or fixed molecular formula [1] [2] [3]. Reports show gelatin is a mixture of variable-length chains (tens to hundreds of residues) built from Gly‑X‑Y collagen-like repeats rather than a single amino‑acid sequence, and its exact composition depends on source and processing [4] [5] [2].
1. What the literature actually names: “gelatin,” not “gelatide”
The search results repeatedly treat “gelatin” as the established term for the material derived from collagen by hydrolysis; none of the cited items use “gelatide” or define it, so available sources do not mention a compound named “gelatide” [1] [2] [6].
2. Why there’s no single chemical structure to give
Gelatin is not a single molecule with a single formula; it is a polydisperse mix of peptides and proteins produced by partial hydrolysis of collagen, so it cannot be represented by one definitive chemical structure or single amino‑acid sequence [2] [3]. Reviews emphasize gelatin’s heterogeneous polypeptide chains of varying lengths and molecular weights produced by different extraction methods [2] [7].
3. Typical sequence motifs and dominant residues
Although gelatin lacks a single sequence, its chains derive from collagen and commonly show the Gly‑X‑Y repeating motif (glycine every third residue) with frequent X/Y positions occupied by proline and 4‑hydroxyproline; typical sequences for model or recombinant gelatins are built from such Gly‑X‑Y repeats [4] [5] [8]. Average amino‑acid composition reports place glycine at roughly one third of residues, with significant fractions of proline and hydroxyproline [9] [10].
4. Examples researchers use: designed or recombinant gelatins
When scientists need a defined sequence, they create artificial or recombinant “gelatins” made of repeating collagen‑like units (examples include 30‑residue designed units PHI and NEU and hexameric repeats based on the Gly‑X‑Y motif) so a precise amino‑acid sequence can exist for engineered gelatin analogues, but these are deliberate constructs distinct from commercial hydrolysed gelatin [11] [8].
5. Practical implications: what you can and cannot claim
You can state that commercial gelatin consists mainly of glycine, proline and hydroxyproline and that it forms gels by helix reformation and aggregated junction zones; those are supported by multiple sources [1] [4] [3]. You cannot supply a single amino‑acid sequence or one structural formula for “gelatin” (and therefore not for an unnamed “gelatide”) because the product is a variable mixture whose sequences depend on species source and processing [2] [7].
6. Why the confusion may arise: naming, engineered variants, and marketing
Confusion often comes from engineered recombinant gelatins, which have defined repeat sequences and are sometimes branded or described differently in patents and company literature; those constructs are documented in the literature (e.g., tandemly repeated 30‑residue units or designed hexamers) but are not the same as bulk gelatin from animal tissues [11] [8]. Marketing or non‑peer sources may invent trade names such as “gelatide,” but available academic and reference sources in the provided set do not corroborate such a term (available sources do not mention “gelatide”).
7. Where to look next if you need a sequence or structure
If you require a precise amino‑acid sequence or atomic structure, consult papers describing recombinant/artificial gelatins (which include explicit sequences like PHI and NEU) or sequence databases for specific collagen alpha chains used as precursors; the cited recombinant studies give concrete unit sequences and production methods [11] [8]. For compositional averages and functional properties of commercial gelatin, use comprehensive reviews and standards [2] [7].
Limitations and transparency: this summary is restricted to the provided search results; none of those sources identify a molecule named “gelatide,” and all factual statements above cite the listed items [1] [2] [6] [4] [3] [7] [5] [11] [8] [9] [10].