RT Journal Article
SR Electronic
T1 Functional metagenomics reveals novel β-galactosidases not predictable from gene sequences
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 047167
DO 10.1101/047167
A1 Jiujun Cheng
A1 Tatyana Romantsov
A1 Katja Engel
A1 Andrew C. Doxey
A1 David R. Rose
A1 Josh D. Neufeld
A1 Trevor Charles
YR 2016
UL http://biorxiv.org/content/early/2016/04/05/047167.abstract
AB A soil metagenomic library carried in pJC8 (an IncP cosmid) was used for functional complementation for β-galactosidase activity in both α-Proteobacteria (Sinorhizobium meliloti) and γ-Proteobacteria (Escherichia coli). One β-galactosidase, encoded by overlapping clones selected in both hosts, was identified as a member of glycoside hydrolase family 2. ORFs obviously encoding possible β-galactosidases were not identified in 19 other clones that were only able to complement S. meliloti. Based on low sequence similarity to known glycoside hydrolases but not β-galactosidases, three ORFs were examined further. Biochemical analysis confirmed that all encoded β-galactosidase activity. Bioinformatic and structural modeling implied that Lac161_ORF10 protein represented a novel enzyme family with a five-bladed propeller glycoside hydrolase domain.CmR(chloramphenicol resistant)GmR(gentamicin resistant)KmR(kanamycin resistant)NmR(neomycin resistant)RifR(rifampicin resistant)SmR(streptomycin resistant)TcR(tetracycline resistant)