scholarly journals Identification of Potent Bactericidal Compounds Produced by Escapin, an l-Amino Acid Oxidase in the Ink of the Sea Hare Aplysia californica

2008 ◽  
Vol 52 (12) ◽  
pp. 4455-4462 ◽  
Author(s):  
Ko-Chun Ko ◽  
Binghe Wang ◽  
Phang C. Tai ◽  
Charles D. Derby
Keyword(s):  
Amino Acid ◽  
Bactericidal Activity ◽  
Aplysia Californica ◽  
Aminocaproic Acid ◽  
Equilibrium Mixture ◽  
Bactericidal Effect ◽  
Low Ph ◽  
Acid Oxidase ◽  
Reaction Products ◽  
Amino Acid Oxidase

ABSTRACT The ink of sea hares (Aplysia californica) contains escapin, an l-amino acid oxidase that metabolizes l-lysine, thereby producing a mixture that kills microbes and deters attacking predators. This secretion contains H2O2, ammonia, and an equilibrium mixture of “escapin intermediate product” (EIP-K) that includes α-keto-ε-aminocaproic acid and several other molecules. Components of the equilibrium mixture react nonenzymatically with H2O2 to form “escapin end product” (EEP-K), which contains δ-aminovaleric acid and δ-valerolactam. The proportions of the molecules in this equilibrium mixture change with pH, and this is biologically important because the secretion is pH 5 when released but becomes pH 8 when fully diluted in seawater. The goal of the current study was to identify which molecules in this equilibrium mixture are bactericidal. We show that a mixture of H2O2 and EIP-K, but not EEP-K, at low mM concentrations is synergistically responsible for most of the bactericidal activity of the secretion against Escherichia coli, Vibrio harveyi, Staphylococcus aureus, and Pseudomonas aeruginosa. Low pH enhances the bactericidal effect, and this does not result from stress associated with low pH itself. Sequential exposure to low mM concentrations of EIP-K and H2O2, in either order, does not kill E. coli. Reaction products formed when l-arginine is substituted for l-lysine have almost no bactericidal activity. Our results favor the idea that the bactericidal activity is due to unstable intermediates of the reaction of α-keto-ε-aminocaproic acid with H2O2.

scholarly journals MipLAAO, a new L-amino acid oxidase from the redtail coral snake Micrurus mipartitus

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e4924 ◽  
Author(s):  
Paola Rey-Suárez ◽  
Cristian Acosta ◽  
Uday Torres ◽  
Mónica Saldarriaga-Córdoba ◽  
Bruno Lomonte ◽  
...  
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Venom Gland ◽  
Bactericidal Effect ◽  
Nucleotide Sequencing ◽  
Acid Oxidase ◽  
Amino Acid Oxidase ◽  
Homologous Proteins ◽  
Edema Formation ◽  
The Difference

L-amino acid oxidases (LAAOs) are ubiquitous enzymes in nature. Bioactivities described for these enzymes include apoptosis induction, edema formation, induction or inhibition of platelet aggregation, as well as antiviral, antiparasite, and antibacterial actions. With over 80 species, Micrurus snakes are the representatives of the Elapidae family in the New World. Although LAAOs in Micrurus venoms have been predicted by venom gland transcriptomic studies and detected in proteomic studies, no enzymes of this kind have been previously purified from their venoms. Earlier proteomic studies revealed that the venom of M. mipartitus from Colombia contains ∼4% of LAAO. This enzyme, here named MipLAAO, was isolated and biochemically and functionally characterized. The enzyme is found in monomeric form, with an isotope-averaged molecular mass of 59,100.6 Da, as determined by MALDI-TOF. Its oxidase activity shows substrate preference for hydrophobic amino acids, being optimal at pH 8.0. By nucleotide sequencing of venom gland cDNA of mRNA transcripts obtained from a single snake, six isoforms of MipLAAO with minor variations among them were retrieved. The deduced sequences present a mature chain of 483 amino acids, with a predicted pI of 8.9, and theoretical masses between 55,010.9 and 55,121.0 Da. The difference with experimentally observed mass is likely due to glycosylation, in agreement with the finding of three putative N-glycosylation sites in its amino acid sequence. A phylogenetic analysis of MmipLAAO placed this new enzyme within the clade of homologous proteins from elapid snakes, characterized by the conserved Serine at position 223, in contrast to LAAOs from viperids. MmipLAAO showed a potent bactericidal effect on S. aureus (MIC: 2 µg/mL), but not on E. coli. The former activity could be of interest to future studies assessing its potential as antimicrobial agent.

scholarly journals Protective Role of d-Amino Acid Oxidase against Staphylococcus aureus Infection

2012 ◽  
Vol 80 (4) ◽  
pp. 1546-1553 ◽  
Author(s):  
Hideaki Nakamura ◽  
Jun Fang ◽  
Hiroshi Maeda
Keyword(s):  
Hydrogen Peroxide ◽  
Staphylococcus Aureus ◽  
Amino Acid ◽  
Bactericidal Activity ◽  
Hypochlorous Acid ◽  
Acid Oxidase ◽  
Amino Acid Oxidase ◽  
Content Type

ABSTRACTd-Amino acid oxidase (DAO) is a hydrogen peroxide-generating enzyme that uses ad-amino acid as a substrate. We hypothesized that DAO may protect against bacterial infection, because hydrogen peroxide is one of the most important molecules in the antibacterial defense systems in mammals. We show here that DAO suppressed the growth ofStaphylococcus aureusin a manner that depended on the concentration of DAO andd-amino acidin vitro. Addition of catalase abolished the bacteriostatic activity of DAO. Although DAO plusd-Ala showed less bactericidal activity, addition of myeloperoxidase (MPO) greatly enhanced the bactericidal activity of DAO. Furthermore, DAO was able to utilize bacterial lysate, which containsd-Ala derived from peptidoglycan; this could produce hydrogen peroxide with, in the presence of myeloperoxidase, formation of hypochlorous acid. This concerted reaction of DAO and MPO led to the bactericidal action.In vivoexperiments showed that DAO−/−(mutant) mice were more susceptible toS. aureusinfection than were DAO+/+(wild-type) mice. These results suggest that DAO, together with myeloperoxidase, may play an important role in antibacterial systems in mammals.

Purification and Characterization of Lupus Anticoagulant Like Protein from Agkistrodon Halys Brevicaudus Venom

1996 ◽  
Vol 76 (06) ◽  
pp. 0993-0997
Author(s):  
Zhao-Yan Li ◽  
Xiao-Wei Wu ◽  
Tie-Fu Yu ◽  
Eric C-Y Lian
Keyword(s):  
Amino Acid ◽  
Lupus Anticoagulant ◽  
Inhibitory Effect ◽  
Clotting Factor ◽  
Acid Oxidase ◽  
Crude Venom ◽  
Amino Acid Oxidase ◽  
Sds Page ◽  
The Individual ◽  
Reducing Condition

SummaryBy means of CM-Sephadex C-25, DEAE-Sephadex A-50, Sephadex G-200, and Sephadex G-75 chromatographies, a lupus anticoagulant like protein (LALP) from Agkistrodon halys brevicaudus was purified. On SDS-PAGE, the purified LALP had a molecular weight of 25,500 daltons under non-reducing condition and 15,000 daltons under reducing condition. The isoelectric point was pH 5.6. Its N terminal amino acid sequencing revealed a mixture of 2 sequences: DCP(P/S)(D/G)WSSYEGH(C/R)Q(Q/K). It was devoid of phospho-lipaseA, fibrino(geno)lytic, 5′-nucleotidase, L-amino acid oxidase, phosphomonoesterase, phosphodiesterase and thrombin-like activities, which were found in crude venom. In the presence of LALP, PT, aPTT, and dRVVT of human plasma were markedly prolonged and its effects were concentration-dependent but time-independent. The inhibitory effect of LALP on the plasma clotting time was enhanced by decreasing phospholipid concentration in TTI test. The individual clotting factor activity was not affected by LALP when higher dilutions of LALP-plasma mixture were used for assay. Russell’s viper venom time was shortened when high phospholipid confirmatory reagent was used. Therefore, the protein has lupus anticoagulant property.

Impairment of Platelet Aggregation by Echis colorata Venom Mediated by L-Amino Acid Oxidase or H2O2

1982 ◽  
Vol 48 (03) ◽  
pp. 277-282 ◽  
Author(s):  
I Nathan ◽  
A Dvilansky ◽  
T Yirmiyahu ◽  
M Aharon ◽  
A Livne
Keyword(s):  
Hydrogen Peroxide ◽  
Amino Acid ◽  
Platelet Aggregation ◽  
Snake Venom ◽  
Oxidase Activity ◽  
Enzyme Preparation ◽  
Acid Oxidase ◽  
Crude Venom ◽  
Amino Acid Oxidase ◽  
Hemostatic Disorders

SummaryEchis colorata bites cause impairment of platelet aggregation and hemostatic disorders. The mechanism by which the snake venom inhibits platelet aggregation was studied. Upon fractionation, aggregation impairment activity and L-amino acid oxidase activity were similarly separated from the crude venom, unlike other venom enzymes. Preparations of L-amino acid oxidase from E.colorata and from Crotalus adamanteus replaced effectively the crude E.colorata venom in impairment of platelet aggregation. Furthermore, different treatments known to inhibit L-amino acid oxidase reduced in parallel the oxidase activity and the impairment potency of both the venom and the enzyme preparation. H2O2 mimicked characteristically the impairment effects of L-amino acid oxidase and the venom. Catalase completely abolished the impairment effects of the enzyme and the venom. It is concluded that hydrogen peroxide formed by the venom L-amino acid oxidase plays a role in affecting platelet aggregation and thus could contribute to the extended bleeding typical to persons bitten by E.colorata.

scholarly journals Spinal mechanisms contributing to the development of pain hypersensitivity induced by sphingolipids in the rat

2021 ◽  
Author(s):  
Hong Wei ◽  
Zuyue Chen ◽  
Ari Koivisto ◽  
Antti Pertovaara
Keyword(s):  
Amino Acid ◽  
Nmda Receptors ◽  
Receptor Antagonist ◽  
Gap Junction ◽  
Male Rats ◽  
Acid Oxidase ◽  
Amino Acid Oxidase ◽  
Mk 801 ◽  
Mechanical Hypersensitivity ◽  
Pain Hypersensitivity

Abstract Background Earlier studies show that endogenous sphingolipids can induce pain hypersensitivity, activation of spinal astrocytes, release of proinflammatory cytokines and activation of TRPM3 channel. Here we studied whether the development of pain hypersensitivity induced by sphingolipids in the spinal cord can be prevented by pharmacological inhibition of potential downstream mechanisms that we hypothesized to include TRPM3, σ1 and NMDA receptors, gap junctions and D-amino acid oxidase. Methods Experiments were performed in adult male rats with a chronic intrathecal catheter for spinal drug administrations. Mechanical nociception was assessed with monofilaments and heat nociception with radiant heat. N,N-dimethylsphingosine (DMS) was administered to induce pain hypersensitivity. Ononetin, isosakuranetin, naringenin (TRPM3 antagonists), BD-1047 (σ1 receptor antagonist), carbenoxolone (a gap junction decoupler), MK-801 (NMDA receptor antagonist) and AS-057278 (inhibitor of D-amino acid oxidase, DAAO) were used to prevent the DMS-induced hypersensitivity, and pregnenolone sulphate (TRPM3 agonist) to recapitulate hypersensitivity. Results DMS alone produced within 15 min a dose-related mechanical hypersensitivity that lasted at least 24 h, without effect on heat nociception. Preemptive treatments with ononetin, isosakuranetin, naringenin, BD-1047, carbenoxolone, MK-801 or AS-057278 attenuated the development of the DMS-induced hypersensitivity, but had no effects when administered alone. Pregnenolone sulphate (TRPM3 agonist) alone induced a dose-related mechanical hypersensitivity that was prevented by ononetin, isosakuranetin and naringenin. Conclusions Among spinal pronociceptive mechanisms activated by DMS are TRPM3, gap junction coupling, the σ1 and NMDA receptors, and DAAO.

scholarly journals Picosecond laser fluorometry of FAD of D-amino acid oxidase-benzoate complex.

1983 ◽  
Vol 258 (6) ◽  
pp. 3799-3802
Author(s):  
K Yagi ◽  
F Tanaka ◽  
N Nakashima ◽  
K Yoshihara
Keyword(s):  
Amino Acid ◽  
Picosecond Laser ◽  
Acid Oxidase ◽  
Amino Acid Oxidase
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