pattern recognition structures

The explanation would be too long and, probably, sophisticated. But I'll try to provide it a little bit later. Liz's reference is correct. Usually, каркас means scaffold, and the quoted term might be translated as 'scaffold-recognizing structures'. But in this field, there is the well-known term 'pattern recognition receptor/structure'.
For more information see https://www.nature.com/articles/s41392-021-00687-0


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Note added at 6 час (2023-12-04 23:37:10 GMT)
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Dylan, in the paper you are translating, there is Ref. 9: “LRR создают каркас-распознающие структуры, но при этом остается достаточное число полипептидных петель между этими повторами, которые и обеспечивают возможность высокоаффинного взаимодействия со структурами различной природы [9]”.
9. Недоспасов С.А. Врожденный иммунитет и его механизмы, Москва, Научный мир, 2012, 21–23. [Nedospasov S. Innate immunity and its mechanisms. Moscow, Scientific world, 2012, 21–23.]
I downloaded this book. Page 23:
2.2 NLR МОЛЕКУЛЫ – ВНУТРИКЛЕТОЧНЫЕ РЕЦЕПТОРЫ И СЕНСОРЫ ВРОЖДЕННОГО ИММУНИТЕТА
Относительно недавно было открыто другое семейство внутриклеточных рецепторов, участвующих в распознавании патогенов и, по-видимому, других внутриклеточных сигналов, которые называются NOD-likr receptors (NLRs) по имени первых молекул этого нового класса NOD1 и NOD2…
Некоторые из этих рецепторов активируются структурными фрагментами патогенов, в частности после их разрушения. Так, NOD1 узнает пептидогликан грамотрицательных бактерий, а NOD2 – мурамилдипептид, фрагмент другого пептидогликана, входящий в состав стенок как грамотрицательных, так и грамположительных бактерий. Пептидогликаны образуют прочный каркас внешней стенки бактерий, и именно эти структуры – уникальные для бактерий – и узнают внутриклеточные рецепторы врожденного иммунитета. Интересно, что NOD1 и NOD2 узнают не только внутриклеточные инфекции, что предполагает доставку компонентов клеточной стенки через клеточную мембрану в цитоплазму.

From this fragment, we see that Nedospasov calls pathogen cell wall components, in particular peptidoglycans, the main structural pathogen fragments that activate innate immunity through binding to NRLs. He writes “Пептидогликаны образуют прочный каркас внешней стенки бактерий”. Here, каркас means a pathogen cell wall component that is composed mainly of peptidoglycans – a peptidoglycan scaffold. In this case, the correct translation would be ‘peptidoglycan scaffold-recognizing structures’. But peptidoglycans are not the only component of the pathogen cell wall which activates innate immunity. So, researchers speak about pathogen patterns (3D structures), which means a variety of cell wall components capable of activating innate immunity.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8813719/
Cell-surface pattern recognition receptors, including receptor-like kinases (RLKs) and receptor-like proteins (RLPs), perceive conserved microbial molecular structures such as pathogen-associated molecular patterns (PAMPs)…

https://www.nature.com/articles/s41392-021-00687-0
PAMPs are the specific and highly conserved molecular structures shared by the same kind of pathogenic microorganisms, including lipids, proteins, and nucleic acids, such as lipopolysaccharides (LPS), lipoteichoic acid (LTA), and bacterial DNA.

Another Nedospasov’s paper: https://link.springer.com/article/10.1134/S1019331613050043
Page 391
Chereshnev explained: it is a true revolution in innate immunity studies. Now we know that innate immunity cells have receptors owing to which they recognize pathogen patterns and, by responding to them, activate the genes of inflammation—the uni versal protective reaction of the organism.

So, to my opinion, you can use both term, pattern recognition structures and (peptide)glycan-recognizing structures for ‘каркас-распознающие структуры’. The difference is that the former term means the whole group of the pathogen cell wall components, whereas the latter means peptidolycans only. ‘Scaffold’ does not work in this case because it requires some explanation.


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Note added at 6 час (2023-12-04 23:49:07 GMT)
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glycan recognition structures
https://www.google.com/search?q=" glycan recognition struct...

peptidoglycan recognition structures
https://www.google.com/search?q=" peptidoglycan recognition ...

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Note added at 16 час (2023-12-05 09:31:14 GMT)
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Regarding your question of distinguishing between pattern and каркас in the text you are translating, "каркас" means a specific spatial structure (3D pattern) recognized by proteins/receptors that activate an immune response. In this context, "scaffold" would mean just a some space frame and, in my opinion, would be much less informative than "pattern".