title: Unexpected Diversity of pepA Genes Encoding Leucine Aminopeptidases in Sediments from a Freshwater Lake.
abstract: We herein designed novel PCR primers for universal detection of the pepA gene, which encodes the representative leucine aminopeptidase gene, and investigated the genetic characteristics and diversity of pepA genes in sediments of hypereutrophic Lake Kasumigaura, Japan. Most of the amino acid sequences deduced from the obtained clones (369 out of 370) were related to PepA-like protein sequences in the M17 family of proteins. The developed primers broadly detected pepA-like clones associated with diverse bacterial phyla-Alpha-, Beta-, Gamma-, and Deltaproteobacteria, Acidobacteria, Actinobacteria, Aquificae, Chlamydiae, Chloroflexi, Cyanobacteria, Firmicutes, Nitrospirae, Planctomycetes, and Spirochetes as well as the archaeal phylum Thaumarchaeota, indicating that prokaryotes in aquatic environments possessing leucine aminopeptidase are more diverse than previously reported. Moreover, prokaryotes related to the obtained pepA-like clones appeared to be r- and K-strategists, which was in contrast to our previous findings showing that the neutral metalloprotease gene clones obtained were related to the r-strategist genus Bacillus. Our results suggest that an unprecedented diversity of prokaryotes with a combination of different proteases participate in sedimentary proteolysis.
authors.affiliation: National Institute for Environmental Studies (NIES), Center for Regional Environmental Research.
authors.forename: Shun
authors.initials: S
authors.lastname: Tsuboi
authors.forename: Shigeki
authors.initials: S
authors.lastname: Yamamura
authors.forename: Akio
authors.initials: A
authors.lastname: Imai
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Iwasaki
mesh_terms: D017931:DNA Primers; D019766:Genes, Archaeal / Q000235:genetics; D005798:Genes, Bacterial / Q000235:genetics; D014644:Genetic Variation; D019015:Geologic Sediments / Q000382:microbiology*; D007564:Japan; D060106:Lakes / Q000382:microbiology*; D007931:Leucyl Aminopeptidase / Q000235:genetics*; D054892:Metagenome; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA
chemical_list: D017931:DNA Primers; D007931:Leucyl Aminopeptidase