This protein is found in eukaryotes. Proteins in this family are typically between 171 to 275 amino acids in length. Although the HsbA amino acid sequence suggests that HsbA may be hydrophilic, HsbA adsorbed to hydrophobic PBSA (Polybutylene succinate-co-adipate) surfaces in the presence of NaCl or CaCl2. When HsbA was adsorbed on the hydrophobic PBSA surfaces, it promoted PBSA degradation via the CutL1 polyesterase. CutL1 interacts directly with HsbA attached to the hydrophobic QCM electrode surface. These results suggest that when HsbA is adsorbed onto the PBSA surface, it recruits CutL1, and that when CutL1 is accumulated on the PBSA surface, it stimulates PBSA degradation.

1: Novel hydrophobic surface binding protein, HsbA, produced by Aspergillus oryzae. Ohtaki S, Maeda H, Takahashi T, Yamagata Y, Hasegawa F, Gomi K, Nakajima T, Abe K; Appl Environ Microbiol. 2006;72:2407-2413. PMID:16597938