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Kazal proteinase inhibitors (KPIs) have been described as important regulators of serine proteinases in invertebrate physiological processes, including the immune response. Several Kazal proteins have been identified in the hemocytes of crustaceans, including freshwater crayfishes, penaeid shrimps, and other shrimps and crabs. Kazal proteins have a repetitive homologous domain structure, and this molecular architecture complicates phylogenetic comparison. Such comparison, with a proper delineation of repeats at the sequence level, however, is important for understanding the structure and function of proteins as well as for the detection of homologous sequences that contribute to explain their evolutionary past. The duplication of coding sequences is a mechanism known to facilitate evolution, and the most important divergence of KPIs appears to be due to insertion, deletion or re-arrangement of complete Kazal domains. A comparison of individual domains, instead of the full protein sequence, thus seems to provide more information and allows a description of the molecular architecture and domain distribution. Considering that each domain undergoes mutation independently, variability in primary sequence via nucleotide substitution is more frequent than the tolerable insertion or deletion of a codon (one amino acid). In addition to primary structure, the distances between Cys residues could therefore be used for domain comparison. Kazal domains from decapod crustaceans are compared using their inter-Cys distances, a nomenclature is proposed for future studies, and the molecular architecture or domain arrangement of these proteins is presented. [ABSTRACT FROM AUTHOR]

Abstract: Mucosal secretions contain a range of defense effector molecules including antimicrobial peptides and proteinase inhibitors. These molecules play a central role in host defense against infection, and in a variety of immune and inflammatory reactions. The aim of this study was to analyze the levels of neutrophil defensins, the cathelicidin hCAP-18/LL-37, and the proteinase inhibitors secretory leukocyte proteinase inhibitor, SKALP/elafin and cystatin M/E in various mucosal secretions and urine. We show here that especially seminal plasma is characterized by high concentrations of hCAP-18/LL-37, SLPI, SKALP/elafin and cystatin M/E. The results of this study demonstrate that each mucosal secretion is characterized by a unique profile of effector molecules, which may supply individual mucosal secretions with specific properties related to the control of local infection and inflammation. [Copyright &y& Elsevier]

Highly active anti-retroviral therapies (HAART) with human immunodeficiency virus (HIV) protease inhibitors (PIs) or nonnucleoside reverse-transcriptase inhibitors (NNRTI) were compared for their effect on prevalence, aspartyl proteinase (Sap) production and the biotypes and anti-mycotic sequential susceptibility of Candida spp. isolates from the oral cavity in a longitudinal prospective study. HAART-PI, but not HAART-NNRTI strongly inhibited Sap expression in the oral cavity without exerting any consistent effect on the role of Candida spp. isolation or selection of low virulence or anti-mycotic resistant fungus biotype. More importantly, the sequential isolates of Candida albicans from HAART-PI, but not those from suspended HAART-NNRTI, showed an increased Sap production in vitro. While further demonstrating that HIV-PI inhibit Sap expressions, our results do not support the view that the mentioned inhibition could eliminate Candida or its selection of the oral cavity. [Copyright &y& Elsevier]

Research into the molecular basis of plant–insect interactions is hampered by the inability to alter the expression of individual genes in plants growing under natural conditions. The ability of virus‐induced gene silencing (VIGS) to silence the expression of two jasmonate‐induced genes known to mediate the expression of two potent direct defences (nicotine and proteinase inhibitors) that are produced in different tissues (roots and shoots, respectively) in Nicotiana attenuata is documented here. Fragments of consensus sequences of N. attenuata’s putrescine N‐methyltransferase (PMT) and trypsin inhibitor (TI) genes were cloned in sense, anti‐sense and inverted repeat orientations into the Tobacco Rattle Virus (TRV) to trigger post‐transcriptional gene silencing by Agrobacterium‐mediated inoculation in plants previously elicited with methyl jasmonate (MeJA) or left as controls. MeJA treatment elicited 2.4‐ and 9.8‐fold increases in the concentrations of nicotine and proteinase inhibitors, respectively, and inoculation with constructs containing appropriate genes inhibited these MeJA‐induced increases and halved constitutive accumulations, regardless of the orientation of the gene fragment. Root PMT transcript levels were significantly elevated in MeJA‐treated plants 10 h after elicitation, but not in plants inoculated with the appropriate TRV constructs 9 d prior to MeJA treatment, demonstrating that VIGS was responsible for the inhibition of these potent direct defences. While additional research is required to minimize the effects on plant growth and the risks of using such constructs in natural settings, it is concluded that VIGS has a potential to manipulate the expression of genes important for ecological interactions. [ABSTRACT FROM PUBLISHER]

Lysosomal proteinases are translated as preproforms, transported through the Golgi apparatus as proforms, and localized in lysosomes as mature forms. In this study, we analyzed which subclass of proteinases participates in the processing of lysosomal proteinases using Bafilomycin Al, a vacuolar ATPase inhibitor. Bafilomycin Al raises lysosomal pH resulting in the degradation of lysosomal proteinases such as cathepsins B, D, and L. Twenty-four hours after the withdrawal of Bafilomycin Al, NIH3T3 cells possess these proteinases in amounts and activities similar to those in cells cultured in DMEM and 5% BCS. In the presence of various proteinase inhibitors, procathepsin processing is disturbed by E-64-d, resulting in abnormal processing of cathepsins D and L, but not by APMSF, Pepstatin A, or CA-074. In the presence of Helicobacter pylori Vac A toxin, which prevents vesicular transport from late endosomes to lysosomes, the processing of procathepsins B and D occurs, while that of procathepsin L does not. Thus, procathepsins B and D are converted to their mature forms in late endosomes, while procathepsin L is processed to the mature form after its arrival in lysosomes by some cysteine proteinase other than cathepsin B. [ABSTRACT FROM PUBLISHER]

The article discusses a study conducted to determine whether gelatinolytic matrix metalloproteinases (MMP) and MMP inhibitors are present in developing corpus luteum in bovines. It is noted that the study also compares the differential activity of gelatinolytic MMP and their inhibitors during luteal development in the bovine estrous cycle.

The article focuses on two experiments that aims to investigate several facts which includes characterization of protein secretion pattern by porcine follicles and corpora lutea and analysis of Mr 30,000 protein by using human chrionic gonadotropin (hCG) hormone. The experiment resulted in the secretion of Mr 30,000 protein which contains the properties same as tissue inhibitor of metalloproteinases-1 (TIMP- 1).