MOTS-c Variants

1 Identity

Compositionally undefined preparation. The parent article is a synthetic 16-residue peptide whose open reading frame is encoded within the mitochondrial 12S ribosomal RNA gene and read in the mitochondrial genetic code; this record, by contrast, names no structure at all. It is filed with biological extracts and compositionally undefined preparations because that is what it is, not because of what it resembles. vendor shorthand for an unnamed analog of the parent. Not a synonym for MOTS-c itself (separate record) and not a synonym for any of the named analogs that genuinely exist in commerce, each of which is a separate article with its own catalog number and its own mass: MOTS-c K14Q, N-acetyl MOTS-c, MOTS-c C-terminal amide, MOTS-c (1-12), MOTS-c (1-13).

Sequence

No defined sequence, and no sequence can honestly be supplied. The source record describes 'minor synthetic structural single amino acid adjustments of standard MOTS-c' and names no variant, no substitution, no substitution position, no formula, no mass and no CAS number. Two suppliers shipping against this record would ship two different compounds and both would conform to it as written. The parent, carried at its own record, is H-Met-Arg-Trp-Gln-Glu-Met-Gly-Tyr-Ile-Phe-Tyr-Pro-Arg-Lys-Leu-Arg-OH (MRWQEMGYIFYPRKLR), free N-terminal alpha-amine, free C-terminal acid, two methionines and no cysteine, therefore no disulfide.

Molecular formula

Not established for this record. No formula can be written for an article with no declared structure. For reference only, the parent is C101H152N28O22S2; that formula belongs to the parent's record. It must not appear on a certificate issued for this preparation.

Average mass

Not established for this record. Reference value for the parent only, from C101H152N28O22S2 on IUPAC 2021 abridged conventional atomic weights (C 12.011, H 1.008, N 14.007, O 15.999, S 32.06): 2174.621 Da. Published figures for the same formula can differ in the second decimal place, because different atomic-weight tables were used to compute them. A published 2174.59, for example, is what the pre-2021 table (C 12.0107, H 1.00794, N 14.0067, O 15.9994, S 32.065) returns for the same formula: 2174.592. The catalog standardizes on the IUPAC 2021 abridged table and states the basis on the face of every mass.

Monoisotopic mass

Not established for this record. Reference value for the parent only: 2173.1077 Da neutral monoisotopic for C101H152N28O22S2; [M+2H]2+ 1087.5612, [M+3H]3+ 725.3765.

Salt / variant note

Everything is a variant here, and that is the finding rather than an evasion of it. Because no structure is declared, each of the following can be shipped under this name and this record cannot call any of them wrong; each is a real, separately cataloged commercial article, and every formula below follows from its own sequence. Human parent, MRWQEMGYIFYPRKLR, C101H152N28O22S2, avg 2174.621 / mono 2173.1077. MOTS-c (Rat), MKRKEMGYIFFSQRTLRNPL, C113H183N33O28S2, avg 2516.030 / mono 2514.3352. MOTS-c (Mouse), MKWEEMGYIFL, C69H99N13O17S2, avg 1446.745 / mono 1445.6723. MOTS-c (1-12), C77H105N17O18S2, avg 1620.908 / mono 1619.7265. MOTS-c (1-13), C83H117N21O19S2, avg 1777.097 / mono 1775.8276. MOTS-c K14Q, C100H148N28O23S2, avg 2174.577 / mono 2173.0714 - 0.036 Da below the parent monoisotopic and therefore indistinguishable from it below roughly 60,000 resolving power. N-acetyl MOTS-c, C103H154N28O23S2, avg 2216.658 / mono 2215.1183, exactly +42.0106 on the parent. MOTS-c C-terminal amide, C101H153N29O21S2, avg 2173.637 / mono 2172.1237, exactly -0.9840 on the parent. A mono- or di-sulfoxide of any of the above at +15.9949 each, twice available because there are two methionines. Acetate and trifluoroacetate salt forms, which some catalogs list as separate items. And CB4211, whose structure is not publicly disclosed and for which no mass can honestly be stated. The masses span 1446.75 to 2516.03 - a 1,069 Da range inside one product name.

2 Class & testing panel

Form

Single article

Testing panel

P7 — panel definition

3 Primary sources & evidence

The index reports the design and provenance of the literature, not a conclusion about effect.

No evidence base can be described, and that absence is the finding rather than a gap in the search. Published literature attaches to a molecule; with no sequence declared there is nothing to search, nothing to cite and no citation-index page to build. Literature does exist for specific named analogs and follows each of them into its own record: the K14Q polymorphism product carries an observational human-genetics literature in Japanese cohort studies, and CohBar's CB4211 has early-phase clinical trial records under its own identifier. Neither body of work is transferable to an unnamed article.

4 Storage & specification

Storage

Not applicable. No article is purchased, received or held under this record, so there is no storage condition to specify. A storage condition is a property of a defined substance and no substance is defined.

Shelf life

Not applicable. A retest interval is a property of a defined substance held under a defined condition, and neither exists here. No retest date can be printed because no lot can be received.