Functional roles of C-terminal extension (CTE) of salt-dependent peptidase activity of the Natrialba magadii extracellular protease (NEP)

OKAMOTO, DEBORA N.; PAGGI, ROBERTO A.; JULIANO, MARIA A.; ICIMOTO, MARCELO Y.; OLIVEIRA, LILIAN C.G.; KONDO, MARCIA Y.; DE CASTRO, ROSANA E.; MAREM, ALYNE; RUIZ, DIEGO M.; GOUVEA, IURI E.; JULIANO, LUIZ

INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES

ELSEVIER SCIENCE BV

Año: 2018 vol. 113 p. 1134 - 1141

0141-8130

Int J Biol Macromol. 2018 Mar 7;113:1134-1141. doi: 10.1016/j.ijbiomac.2018.03.026. [Epub ahead of print]Functional roles of C-terminal extension (CTE) of salt-dependent peptidase activity of the Natrialba magadii extracellular protease (NEP).Marem A1, Okamoto DN1, Oliveira LCG1, Ruiz DM2, Paggi RA3, Kondo MY1, Gouvea IE1, Juliano MA1, de Castro RE3, Juliano L1, Icimoto MY4.Author informationAbstractNep (Natrialba magadii extracellular protease) is a halolysin-like peptidase secreted by the haloalkaliphilic archaeon Natrialba magadii. Many extracellular proteases have been characterized from archaea to bacteria as adapted to hypersaline environments retaining function and stability until 4.0M NaCl. As observed in other secreted halolysins, this stability can be related to the presence of a C-terminal extension (CTE) sequence. In the present work, we compared the biochemical properties of recombinant Nep protease with the truncated form at the 134 amino acids CTE (Nep∆CTE), that was more active in 4M NaCl than the non-truncated wild type enzyme. Comparable to the wild type, Nep∆CTE protease is irreversibly inactivated at low salt solutions. The substrate specificity of the truncated Nep∆CTE was similar to that of wild type form as demonstrated by a combinatorial library of FRET substrates. The enzyme stability, the effect of different salts and the thermodynamics assays using different lengths of substrates demonstrated similarities between the two forms. Altogether, these data provide further information on the stability and structural determinants of halolysins under different salinities, especially concerning the enzymatic behavior.KEYWORDS:Haloalkaliphilic protease; Natrialba magadii; Serine proteasePMID:29524492 DOI:10.1016/j.ijbiomac.2018.03.026