Proteases play important roles in parasite development and host parasite interactions. The protease of Kudoa spp. has been recognized as a key factor of severe proteolysis of fish muscle post-mortem; however, there is little information available regarding the protease of Kudoa (K.) septempunctata, which was recently identified as a cause of food poisoning in humans. The present study was conducted to isolate and characterize proteases to elucidate the type of protease contained in the parasite and determine the optimal pH for protease activity. We confirmed the cysteine protease and metalloprotease produced by K. septempunctata. While the cysteine protease showed optimal activity at pH 5 that decreased rapidly with increasing pH, the optimal activity of metalloprotease was pH 7, and it remained stable from pH 6 to pH 8. These results indicate that the pH of cysteine protease is not proper for fish muscle postmortem, and that metalloprotease can act in human intestines. Overall, the present study provides important information that improves our understanding of the role of protease physiology and the subsequent food poisoning caused by K. septempunctata.
Cysteine Proteases ; Foodborne Diseases ; Host-Parasite Interactions ; Humans ; Hydrogen-Ion Concentration ; Intestines ; Parasites ; Peptide Hydrolases* ; Physiology ; Proteolysis

The picornavirus family comprises many small viruses, several of which are important pathogens of humans and livestock. The 3C protease (3Cpro) of different species and genera of picornavirus contains the classic G-X-C-G motif and Cys-His-Asp/Glu catalytic triad. 3Cpro conducts maturation cleavage in the regions of VP2-VP3 and VP3-VP1 in P1, 2A-2B and 2B-2C in P2 and the whole P3. Picornavirus 3Cpro has been shown to have significant substrate preference in Q-G/S/A/V/H/R and E-S/G/R/M as well as species and genera specificity through analyses of the maturation cleavage of picornavirus polyproteins. Innate immune adaptors such as TRIF, MAVS, IRF3, IRF7 and NEMO have various potential cleavage sites in picornavirus 3Cpro (TRIF and NEMO show considerable diversity in their cleavage sites). Useful information will be provided for the development of broad-spectrum antiviral agents as well as evasion mechanisms of the innate immune system against picornavirus 3Cpro through continued research of picornavirus 3Cpro.
Cysteine Endopeptidases ; physiology ; Immunity, Innate ; Picornaviridae ; enzymology ; immunology ; Viral Proteins ; physiology ; Virus Replication

Streptococcus mutans is a common Gram-positive bacterium and plays a significant role in dental caries. Tobacco and/or nicotine have documented effects on S. mutans growth and colonization. Sortase A is used by many Gram-positive bacteria, including S. mutans, to facilitate the insertion of certain cell surface proteins, containing an LPXTGX motif such as antigen I/II. This study examined the effect of nicotine on the function of sortase A to control the physiology and growth of S. mutans using wild-type S. mutans NG8, and its isogenic sortase-defective and -complemented strains. Briefly, the strains were treated with increasing amounts of nicotine in planktonic growth, biofilm metabolism, and sucrose-induced and saliva-induced antigen I/II-dependent biofilm formation assays. The strains exhibited no significant differences with different concentrations of nicotine in planktonic growth assays. However, they had significantly increased (P≤0.05) biofilm metabolic activity (2- to 3-fold increase) as the concentration of nicotine increased. Furthermore, the sortase-defective strain was more sensitive metabolically to nicotine than the wild-type or sortase-complemented strains. All strains had significantly increased sucrose-induced biofilm formation (2- to 3-fold increase) as a result of increasing concentrations of nicotine. However, the sortase-defective strain was not able to make as much sucrose- and saliva-induced biofilm as the wild-type NG8 did with increasing nicotine concentrations. These results indicated that nicotine increased metabolic activity and sucrose-induced biofilm formation. The saliva-induced biofilm formation assay and qPCR data suggested that antigen I/II was upregulated with nicotine but biofilm was not able to be formed as much as wild-type NG8 without functional sortase A.
Amino Acid Motifs ; Aminoacyltransferases ; drug effects ; genetics ; Antigens, Bacterial ; drug effects ; Bacterial Adhesion ; drug effects ; Bacterial Proteins ; drug effects ; genetics ; Biofilms ; drug effects ; Cysteine Endopeptidases ; drug effects ; genetics ; Dose-Response Relationship, Drug ; Humans ; Mutation ; genetics ; Nicotine ; administration & dosage ; pharmacology ; Peptidoglycan ; drug effects ; genetics ; Saliva ; physiology ; Streptococcus mutans ; drug effects ; enzymology ; growth & development ; Sucrose ; pharmacology

Fascioliasis is one of the public health problems in the world. Cysteine proteinases (CP) released by Fasciola gigantica play a key role in parasite feeding, migration through host tissues, and in immune evasion. There has been some evidence from several parasite systems that proteinases might have potential as protective antigens against parasitic infections. Cysteine proteinases were purified and tested in vaccine trials of sheep infected with the liver fluke. Multiple doses (2 mg of CP in Freund's adjuvant followed by 3 booster doses 1 mg each at 4 week intervals) were injected intramuscularly into sheep 1 week prior to infect orally with 300 F. gigantica metacercariae. All the sheep were humanely slaughtered 12 weeks after the first immunization. Changes in the worm burden, ova count, and humoral and cellular responses were evaluated. Significant reduction was observed in the worm burden (56.9%), bile egg count (70.7%), and fecel egg count (75.2%). Immunization with CP was also found to be associated with increases of total IgG, IgG1, and IgG2 (P<0.05). Data showed that the serum cytokine levels of pro-inflammatory cytokines, IL-12, IFN-gamma, and TNF-alpha, revealed significant decreases (P<0.05). However, the anti-inflammatory cytokine levels, IL-10, TGF-beta, and IL-6, showed significant increases (P<0.05). In conclusion, it has been found that CP released by F. gigantica are highly important candidates for a vaccine antigen because of their role in the fluke biology and host-parasite relationships.
Animals ; Antibodies, Helminth/immunology ; Cysteine Proteases/administration & dosage/*immunology/isolation & purification ; Cytokines/immunology ; Fasciola/chemistry/*enzymology/immunology ; Fasciola hepatica/immunology/physiology ; Fascioliasis/immunology/parasitology/*prevention & control ; Female ; Helminth Proteins/administration & dosage/*immunology/isolation & purification ; Humans ; Male ; Protective Agents/*administration & dosage/isolation & purification ; Sheep ; Vaccines/immunology

OBJECTIVE[corrected] To investigate the role of glutathione (GSH) and γ-glutamylcysteine synthetase (γ-GCS) in lupus nephritis.

METHODSSpectrophotometry was used to measure the oxidative/anti-oxidative indices including malonyldialdehyed (MDA) and GSH in the kidney of MRL/lpr lupus mice. Quantitative PCR and Western blotting were used to detected the expression of γ-GCS.

RESULTSThe level of GSH was lowered whereas the level of MDA increased significantly in the kidney tissue of MRL/lpr lupus mice as compared with that in normal control mice. The expression of γ-GCS mRNA and protein was significantly decreased in MRL/lpr lupus mice (P<0.05).

CONCLUSIONMRL/lpr lupus mice have abnormal oxidative stress in the kidney tissue, where the expression of γ-GCS decreased to lead to reduced GSH production, damaged antioxidative capacity, and eventually exacerbation of oxidative damage in the kidney.

Animals ; Glutamate-Cysteine Ligase ; genetics ; metabolism ; Glutathione ; metabolism ; Kidney ; enzymology ; metabolism ; Lupus Nephritis ; enzymology ; metabolism ; Malondialdehyde ; metabolism ; Mice ; Mice, Inbred MRL lpr ; Oxidative Stress ; physiology ; RNA, Messenger ; genetics ; metabolism

Bacterial biofilms can be viewed as a specific type of persistent bacterial infection. After initial invasion, microbes can attach to living and non-living surfaces, such as prosthetics and indwelling medical devices, and form a biofilm composed of extracellular polysaccharides, proteins, and other components. In hosts, biofilm formation may trigger drug resistance and inflammation, resulting in persistent infections. The clinical aspects of biofilm formation and leading strategies for biofilm inhibitors will be discussed in this mini-review.
Adhesins, Bacterial ; drug effects ; physiology ; Aminoacyltransferases ; antagonists & inhibitors ; genetics ; Animals ; Antimicrobial Cationic Peptides ; genetics ; pharmacology ; Bacterial Infections ; microbiology ; surgery ; Bacterial Proteins ; antagonists & inhibitors ; genetics ; Biofilms ; drug effects ; growth & development ; Chronic Disease ; Cysteine Endopeptidases ; genetics ; Cysteine Proteinase Inhibitors ; pharmacology ; Humans ; Inflammation ; microbiology ; Quorum Sensing ; drug effects ; physiology ; Wound Infection ; microbiology ; surgery

BACKGROUNDAutism spectrum disorders (ASD), which include autism, asperger syndrome (AS) and pervasive developmental disorder-not otherwise specified (PDD-NOS), are devastating neurodevelopmental disorders of childhood resulting in deficits in social interaction, repetitive patterns of behaviors, and restricted interests and activities. Single photon emission computed tomography (SPECT) is a common technique used to measure regional cerebral blood flow (rCBF). Several studies have measured rCBF in children with ASD using SPECT, however, findings are discordant. In addition, the majority of subjects used in these studies were autistic. In this study, we aimed to investigate changes in rCBF in children with ASD using SPECT.

METHODSA Technetium-99m-ethyl cysteinate dimmer (⁹⁹m)Tc-ECD) brain SPECT study was performed on an ASD group consisting of 23 children (3 girls and 20 boys; mean age (7.2 ± 3.0) years) who were diagnosed according to Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV) criteria and an age-matched control group with 8 children (1 girl and 7 boys, mean age (5.5 ± 2.4) years). Image data were evaluated with Statistical Parametric Mapping, 5th version (SPM5). A Student's t test for unpaired data was used to compare rCBF and asymmetry in the autism and corresponding control group. The covariance analysis, taking age as covariance, was performed between the ASD and control group.

RESULTSThere was a significant reduction in rCBF in the bilateral frontal lobe (frontal poles, arcula frontal gyrus) and the bilateral basal ganglia in the autism group, and a reduction in the bilateral frontal, temporal, parietal, legumina nucleus and cerebellum in the AS group compared to the control. In addition, asymmetry of hemispheric hypoperfusion in the ASD group was observed. Inner-group comparison analysis revealed that rCBF decreased significantly in the bilateral frontal lobe (42.7%), basal nucleus (24.9%) and temporal lobe (22.8%) in the autism group, and in the bilateral cerebellum (22.8%), basal nucleus (19.3%) and right thalamencephalon (16.6%) in the AS group (P < 0.05).

CONCLUSIONSThe decrease in rCBF in ASD is a global event, which involves the bilateral frontal, temporal, limbic system and basal ganglias. Asymmetry of hemispheric hypoperfusion was more obvious in the AS group than the autism group, which indicates a different neurobiological mechanism from that of autism.

Cerebrovascular Circulation ; physiology ; Child ; Child Development Disorders, Pervasive ; pathology ; physiopathology ; Child, Preschool ; Cysteine ; analogs & derivatives ; Female ; Humans ; Male ; Organotechnetium Compounds ; Regional Blood Flow ; physiology ; Tomography, Emission-Computed, Single-Photon ; methods

Adult ; Asthma ; metabolism ; physiopathology ; Basic-Leucine Zipper Transcription Factors ; genetics ; physiology ; Fanconi Anemia Complementation Group Proteins ; genetics ; physiology ; Female ; Glutamate-Cysteine Ligase ; metabolism ; Humans ; Inflammation ; metabolism ; pathology ; Male ; NF-E2-Related Factor 2 ; genetics ; physiology ; RNA, Messenger ; genetics ; metabolism ; Sputum ; cytology

Small ubiquitin-like modifier protein (SUMO) modification is a highly dynamic process, catalyzed by SUMO-specific activating (E1), conjugating (E2) and ligating (E3) enzymes, and reversed by a family of SUMO-specific proteases (SENPs). There are six members of the human SENP family, and each SENP has different cellular locations and substrate specificities. However, the precise roles of SENPs in cellular processes have not been elucidated to date. This brief review will focus on recent advances pertaining to the identified targets of SENP1 and its potential role in prostate cancer.
Cysteine Endopeptidases ; Endopeptidases ; physiology ; Humans ; Hypoxia-Inducible Factor 1, alpha Subunit ; physiology ; Male ; Prostatic Neoplasms ; physiopathology ; Receptors, Androgen ; physiology ; SUMO-1 Protein ; physiology ; Signal Transduction ; physiology

AIMTo complete comprehensive haplotype analysis of USP26 for both fertile and infertile men.

METHODSTwo hundred infertile men with severe oligospermia or non-obstructive azoospermia were subjected to sequence analysis for the entire coding sequences of the USP26 gene. Two hundred men with proven fertility were genotyped by primer extension methods. Allele/genotype frequencies, linkage disequilibrium (LD) characteristics and haplotypes of fertile men were compared with infertile men.

RESULTSThe allele frequencies of five single nucleotide polymorphisms (370-371insACA, 494T>C, 576G>A, ss6202791C>T, 1737G>A) were significantly higher in infertile patients than control subjects. The major haplotypes in infertile men were TACCGA (28% of the population), TGCCGA (15%), TACCAA (8%), TGCCAA (6%), TATCAA (5%) and CATCAA (5%). The major haplotypes for the control subjects were TACCGA (58% of the population), CACCGA (7%), CATCGA (6%) and TGCCGA (5%). Haplotypes TGCCGA, TATCAA, CATCAA, CATCGC, TACCAA and TGCCAA were over-transmitted in patients with spermatogenic defect, whereas haplotypes TACCGA, CACCGA, and CATCGA were under-transmitted in these patients.

CONCLUSIONSome USP26 alleles and haplotypes are associated with spermatogenic defect in the Han nationality in Taiwan, China.

Adult ; Alleles ; Azoospermia ; epidemiology ; genetics ; Cysteine Endopeptidases ; genetics ; DNA Primers ; Gene Frequency ; Genetic Variation ; Genotype ; Haplotypes ; Humans ; Infertility, Male ; epidemiology ; genetics ; Linkage Disequilibrium ; Male ; Multigene Family ; Oligospermia ; epidemiology ; genetics ; Polymorphism, Genetic ; Spermatogenesis ; genetics ; physiology ; Taiwan ; epidemiology