Complestatin-Family BGC LBP-Chassis Feasibility (comp-024)

COMP-024 is invalidated and non-runnable. Its hand-assigned factors, geometric means, color thresholds, host ordering, and C1-INH comparison have no predictive or decision status. The model does not establish that an LBP route fails, that another host wins, or that C1-INH should receive priority.

Evidence that survives

Chiu et al. described a 48.7 kb complestatin biosynthetic gene cluster with 16 open reading frames and seven NRPS modules (In Vitro molecular and biochemical characterization; PMID 11447274). Park et al. reconstituted a 54.5 kb cluster in Streptomyces lividans TK24; their gene-deletion experiments produced the monocyclic derivative M55 and linear derivative S56 (In Vitro heterologous production and structural characterization; PMID 27383040). The accessible primary record does not establish that either derivative lacked biological activity.

These records support treating complete tailoring and active-product recovery as experimental gates. They do not establish transfer to E. coli Nissle 1917 or Bacteroides thetaiotaomicron, nor do they show that either host is incapable of producing the molecule.

Research conjecture — production phase may determine complestatin viability

Grounded premises: The complestatin cluster includes cytochrome P450 genes, and Park et al. showed that deleting two of those genes changed the recovered products to monocyclic M55 and linear S56 (In Vitro; source: PMID 27383040). Cytochrome P450 catalysis is oxygen-dependent (Mechanistic Extrapolation; source: established P450 reaction chemistry). S. lividans TK24 produced products from the reconstituted cluster under the tested manufacturing conditions (In Vitro; source: PMID 27383040). Transfer to an LBP chassis has not been demonstrated.

Novel leap: Active complestatin may require an oxygenated manufacturing phase even if the eventual product is delivered to an anaerobic compartment. No direct evidence establishes complete active-product formation in EcN or Bacteroides.

Why it matters: This separates the molecule from the production chassis. Failure of live colonic manufacture would not by itself kill an ex-situ production-and-delivery route.

Discriminating observation: In a prespecified host × oxygen-regime matrix, measure intact crosslinked product by analytical chemistry, complement-inhibitory activity, production rate, and host fitness. Advance the active-product-formation hypothesis only if active product—not merely expressed genes or linear peptide—is recovered. Delivery, compartmental access, safety, and portfolio priority require separate evidence.

C1-INH remains a separate CP0 candidate. Its exact construct, folding, glycosylation dependence, luminal stability, retained inhibition, and access require their own measurements; COMP-024 supplies none of them.