Identification and Characterization of Human Archaemetzincin-1 and -2, Two Novel Members of a Family of Metalloproteases Widely Distributed in Archaea

Abstract

Systematic analysis of degradomes, the complete protease repertoires of organisms, has demonstrated the large and growing complexity of proteolytic systems operating in all cells and tissues. We report here the identification of two new human metalloproteases that have been called archaemetzincin-1 (AMZ1) and archaemetzincin-2 (AMZ2) to emphasize their close relationship to putative proteases predicted by bioinformatic analysis of archaeal genomes. Both human proteins contain a catalytic domain with a core motif (HEXXHXXGX 3 CX 4 CXMX 17 CXXC) that includes an archetypal zinc-binding site, the methionine residue characteristic of metzincins, and four conserved cysteine residues that are not present at the equivalent positions of other human metalloproteases. Analysis of genome sequence databases revealed that AMZs are widely distributed in Archaea and vertebrates and contribute to the defining of a new metalloprotease family that has been called archaemetzincin. However, AMZ-like sequences are absent in a number of model organisms from bacteria to nematodes. Phylogenetic analysis showed that these enzymes have undergone a complex evolutionary process involving a series of lateral gene transfer, gene loss, and genetic duplication events that have shaped this novel family of metalloproteases. Northern blot analysis showed that AMZ1 and AMZ2 exhibit distinct expression patterns in human tissues. AMZ1 is mainly detected in liver and heart whereas AMZ2 is predominantly expressed in testis and heart, although both are also detectable at lower levels in other tissues. Both human enzymes were produced in Escherichia coli, and the purified recombinant proteins hydrolyzed synthetic substrates and bioactive peptides, demonstrating that they are functional proteases. Finally, these activities were abolished by inhibitors of metalloproteases, providing further evidence that AMZs belong to this catalytic class of proteolytic enzymes.

Ribosomal Protein S27-Like in Colorectal Cancer: A Candidate for Predicting Prognoses

“…Further, shRPS27L does not affect the expression of any other genes, even those (klotho, NM_004795; archaelysin family metallopeptidase 1, NM_133463) with mRNA sequences that have partial matches to shRPS27L (Figure S3). In fact, klotho and archaelysin family metallopeptidase 1 are naturally expressed at low levels in our target CRC cell line, LoVo (data not shown) [27], [28]. Overall, our results confirm that the effects of shRPS27L are specific.…”

High levels of mineralocorticoids in preovulatory follicular fluid could contribute to oocyte development

“…Comparing the level of mRNA content in young versus old patients favored production of aldosterone and the accumulation of corticosterone in young patients. The magnitude of changes and the specific gene functions (20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30)(31)(32)(33)(34) for differentially expressed mRNAs are summarized in Table 1. Of note, the mRNA expression in the corticosterone quantity pathway is primarily associated with genes that inhibit accumulation.…”

Crystal structure of archaemetzincin amza from Methanopyrus kandleri at 1.5 Å resolution

“…3 Human archaemetzincin-1 and archaemetzincin-2 were shown to have aminopeptidase activity. 6 On the other hand, archaemetzincin from Mycococcus xanthus presents an interesting example of a protein with the metzincin fold that has lost its ability to hydrolyze peptide bonds and has evolved into a zinc-binding transcription factor with the metal fulfilling only a structural role. 7 Seven of the known metzincin families have been structurally characterized to date.…”