Identification of a novel transglutaminase from the filarial parasite Brugia malayi andits role in growth and development

Transglutaminase-catalyzed reaction is important for molting of Onchocerca volvulus third-stage larvae

“…Recently, an active TGase from an adult B. malayi worm was biochemically purified and characterized and its partial amino acid sequence was determined (37). In previous studies (29,31), it was reported that TGase inhibitors were lethal to B. malayi L3 and, in B. malayi and A. viteae, also affected other stages of development, microfilaria production, and microfilaria release by gravid female worms. In addition, an indirect support for the importance of TGase-catalyzed reactions for the molting of Onchocerca larvae could be derived from the report by Lok et al (24), showing that synthetic retinoids can inhibit the L3 to L4 molt of O. lienalis in vitro.…”

“…The presence of putative TGases and the products of TGase-catalyzed reactions was reported in other filarial nematodes (29,31,41). More recently, an active Brugia malayi TGase with a molecular mass of 56 kDa was purified (37).…”

“…More recently, an active Brugia malayi TGase with a molecular mass of 56 kDa was purified (37). Numerous ε-(␥-glutamyl)lysine isopeptide bonds were detected in adult worm extracts of B. malayi (29) and in sheaths of Litomosoides carinii microfilariae (41). Furthermore, embryos developing in utero contained very high amounts of the enzyme (29).…”

“…Furthermore, embryos developing in utero contained very high amounts of the enzyme (29). Inhibition of enzyme activity in vitro by monodansylcadaverine (MDC) and cystamine (CS), two specific inhibitors of TGase (13,25,40), led to a time-and dose-dependent inhibition of microfilarial production and release by gravid female B. malayi and Acanthocheilonema viteae (29,31), thus indicating that in these parasites, TGase-catalyzed reac-tions play an important role during embryogenesis, the maturation of early embryonic stages to microfilariae, and survival of the parasites.…”

A Transglutaminase Immunologically Related to Tissue Transglutaminase Catalyzes Cross-Linking of Cell Wall Proteins inChlamydomonas reinhardtii

“…One of the most conserved domains of the TGase enzyme at the amino acid level corresponds to the active site, and DNA probes from this region have been used to clone TGases from different organisms (Floyd and Jetten, 1989;Kim et al, 1991). Perhaps the antigenicity of this domain is the reason why antibodies to animal TGases cross-react with homologs in filarial parasites (Mehta et al, 1992), higher plants (Del Duca et al, 1994, Dunaliella salina (Serafini-Fracassini et al, 1995), and C. reinhardtii. To date, only intracellular TGases have been reported in higher plants (Serafini-Fracassini et al, 1995;Del Duca et al, 1997;Hou and Lin, 1997).…”