Abh, AbrB3, and Spo0A play distinct regulatory roles during polymyxin synthesis in SC2.

Polymyxins are considered the last line of defense against multidrug-resistant bacteria. The regulatory mechanism of polymyxin synthesis is poorly studied in . In this study, we found that Abh and AbrB3 negatively regulated, whereas Spo0A positively regulated polymyxin synthesis in SC2.

The Impact of Growth Years on the Medicinal Material Characteristics and Metabolites of L. var. Bge. Reveals the Optimal Harvest Age.

The original plant of Chinese medicine Stellariae Radix (Yin Chai Hu) is L. var. Bge (abbreviated as SDL).

Comparative metabolomics provides novel insights into correlation between dominant habitat factors and constituents of ( L. var. Bge.).

L. var. Bge.

Synergistic effect of co-culture rhizosphere : A promising strategy to enhance antimicrobial activity and plant growth-promoting function.

Rhizosphere is one of the important types of rhizosphere microorganisms that plays an important role in promoting plant growth and controlling plant diseases to maintain agricultural ecosystem balance and green ecological agriculture development as beneficial bacteria. Microbial co-culture simulates the complex biocommunity in nature, which has more advantages than the monoculture with a synergistic effect. As the key signal mediums of microorganisms, plants, and their interactions, microbial metabolites are of great significance in revealing their functional mechanism.

Flavoenzyme CrmK-mediated substrate recycling in caerulomycin biosynthesis.

Substrate salvage or recycling is common and important for primary metabolism in cells but is rare in secondary metabolism. Herein we report flavoenzyme CrmK-mediated shunt product recycling in the biosynthesis of caerulomycin A (CRM A ), a 2,2'-bipyridine-containing natural product that is under development as a potent novel immunosuppressive agent. We demonstrated that the alcohol oxidase CrmK, belonging to the family of bicovalent FAD-binding flavoproteins, catalyzed the conversion of an alcohol into a carboxylate an aldehyde.

Biochemical and Structural Insights into the Aminotransferase CrmG in Caerulomycin Biosynthesis.

Caerulomycin A (CRM A 1) belongs to a family of natural products containing a 2,2'-bipyridyl ring core structure and is currently under development as a potent novel immunosuppressive agent. Herein, we report the functional characterization, kinetic analysis, substrate specificity, and structure insights of an aminotransferase CrmG in 1 biosynthesis. The aminotransferase CrmG was confirmed to catalyze a key transamination reaction to convert an aldehyde group to an amino group in the 1 biosynthetic pathway, preferring l-glutamate and l-glutamine as the amino donor substrates.

Acyclic congeners from Actinoalloteichus cyanogriseus provide insights into cyclic bipyridine glycoside formation.

Inactivation of the O-methyltransferase gene crmM of Actinoalloteichus cyanogriseus WH1-2216-6 led to a mutant that produced three new acyclic bipyridine glycosides, cyanogrisides E-G (1-3). Further chemical analysis of the wild strain yielded 1 and another new analogue, cyanogriside H (4). Compounds 1-4 possess a skeleton consisting of a 2,2'-bipyridine and a d-quinovose or l-rhamnose sugar moiety.