A molecular key for building hyphae aggregates: the role of the newly identified Streptomyces protein HyaS.
Bottom Line: The HyaS protein is dominantly associated with the substrate hyphae.Investigations of ΔH transformants, each carrying a specifically mutated gene, lead to the conclusion that the in situ oxidase activity correlates with the pellet-inducing role of HyaS, and depends on the presence of certain histidine residues.These data present the first molecular basis for future manipulation of pellets, and concomitant production of secondary metabolites during biotechnological processes.
Affiliation: University of Osnabrück, FB Biology/Chemistry, Applied Genetics of Microorganisms, 49069 Osnabrück, Germany.Show MeSH
Related in: MedlinePlus
Mentions: To test whether the presence of full‐length HyaS provoked the production of H2O2 based on an endogenous, but so far unknown substrate within the natural host, pre‐grown hyphae of transformants of ΔH were exposed to 3,3′ diaminobenzidine (DAB), which is known to polymerize in the presence of H2O2 (Rea et al., 2002). The hyaS‐negative strain ΔH with the control plasmid pWHM3 (Fig. 7C) appeared light yellowish (i.e. background). In contrast, the WT strain with the control plasmid pWHM3 (Fig. 7A), contained among lighter brown pellets a high portion that stained intensively red‐brown, reflecting high level of generated H2O2. The data indicated that the presence of the hyaS gene in the WT strain provoked this feature.
Affiliation: University of Osnabrück, FB Biology/Chemistry, Applied Genetics of Microorganisms, 49069 Osnabrück, Germany.