Purification and characterization of phenoloxidase from clam Ruditapes philippinarum

Purification and characterization of phenoloxidase from <italic>Octopus ocellatus</italic>

“…The optimal pH of purified Octopus PO was 7.0 against L-DOPA which was similar to that of Ruditapes philippinarum [17] and colonial ascidian Botryllus schlosseri ( pH 7.0-7.5) [29], higher than that of P. chinensis ( pH 6.0) [16] and Charybdis japonica ( pH 6.0) [18], and lower than that of Penaeus setiferus ( pH 7.5) [30], Illex argentinus ( pH 8.0) [28], brown shrimp ( pH 8.0) [22], and Heliothis virescens ( pH 9.5) [31]. The purified Octopus PO had an optimum temperature of 408C coinciding with that of Japanese prawn [32], P. chinensis [16], C. japonica [18], and R. philippinarum [17], higher than that of Drosophila melanogaster (308C) [33], and lower than that of Chlamys farreri (458C) [34] and P. setiferus (458C) [30].…”

“…In all cases where the inactive proenzyme has been purified, the monomer has a molecular mass of 70-87 kDa, and after proteolytic activation, the active enzyme, PO, has a molecular mass of 60-77 kDa [15][16][17][19][20][21]. The PO from brown shrimp Penaeus californiensis was classified as a tyrosinase type of PO [22] and the PO of shrimp Penaeus chinensis and clam Ruditapes philippinarum is a tyrosinase-type of metalloenzyme [16,17].…”

CHARACTERIZATION OF CRUDE EXTRACT POLYPHENOLOXIDASE ENZYME FROM BLACK TIGER SHRIMP (Penaeus monodon)

“…L-DOPA memiliki kemampuan berikatan yang lebih baik dibandingkan dengan substrat lain. Cong et al (2005) (Martinez dan Whitaker, 1995). Polyphenoloxidase bertanggung jawab untuk mengkatalis terjadinya dua reaksi dasar.…”

“…Kinetika enzim berdasarkan persamaan Lineweaver-Burk menunjukan bahwa Km enzim PPO dari Penaeus monodon sebesar 5,42 mM (Gambar 7). Nilai K m ini masih lebih rendah dibandingkan dengan beberapa penelitian lain, seperti enzim pada Ruditapes philippinarum sebesar 2,2 mmol/L (Cong et al, 2005), Charybdis japonica sebesar 2,90 mM (Fan et al, 2009), Penaeus vannamei sebesar 1,47 mM (GarciaCarreno et al, 2008), Parapenaeus longirostris sebesar 1,85 mM (Zamorano et al, 2009 …”

“…Enzim memiliki aktivitas tertinggi pada pH 4,5 serta stabil pada pH 4,5 dan 9,0. Cong et al (2005) menyatakan phenoloxidase dari hemolymph Ruditapes philippinarum optimum pada pH 7. Fan et al (2011) menyatakan PO Artemia sinica optimal pada pH 7.…”