当前位置： SCI文献检索 > MOLECULAR AND BIOCHEMICAL PARASITOLOGY期刊下所有文献 > Excystation of Eimeria acervulina, E. maxima, and E. tenella differs in response to trypsin and chymotrypsin and the presence of reducing agents DTT and TCEP.

Excystation of Eimeria acervulina, E. maxima, and E. tenella differs in response to trypsin and chymotrypsin and the presence of reducing agents DTT and TCEP.

Abstract：

:Release of sporozoites from Eimeria oocysts/sporocysts is an essential step in the intracellular development of the parasite in its host. Little is known about this process except that elevated temperature (∼ 40 °C) plus trypsin and bile salts are required for sporozoite to escape from sporocysts. In this study, it was found that adding a reducing agent, either dithiothreitol (DTT) or Tris(2-carboxyethyl)phosphine hydrochloride (TCEP), increased the lifespan of sporozoites released from Eimeria maxima. While the addition of DTT or TCEP affected the apparent molecular weight of trypsin, it did not interfere with excystation of E. maxima, but rather had a positive effect on the number of viable sporozoites present after release. This effect was time-dependent in that the number of intact sporozoites at 15 and 30 min after excystation was similar between untreated and DTT- or TCEP-treated sporocysts. However, by 45-60 min, virtually no sporozoites were observed in excystation fluid not containing DTT or TCEP. Of interest is that this effect appeared to be Eimeria species-dependent. Eimeria acervulina and E. tenella sporozoites remained viable for at least 60 min after excystation in the absence of DTT or TCEP. The effect of DTT and TCEP on chymotrypsin was also studied with all 3 Eimeria species because there is some evidence that chymotrypsin is an effective excystation enzyme. Indeed, E. maxima sporozoites excysting from sporocysts with chymotrypsin in the presence of DTT or TCEP remained viable for at least 60 min after release, unlike excystation done in the absence of these reducing agents. Chymotrypsin was capable of excysting E. acervulina in the presence or absence of DTT or TCEP. Of interest, is that chymotrypsin was ineffective in the excystation of E. tenella. These findings suggest that trypsin and chymotrypsin have differential effects on sporozoite excystation and that reducing agents may alter sites on the enzyme that affect sporozoite viability, but not release from sporocysts.

journal_name

Mol Biochem Parasitol

journal_title

Molecular and biochemical parasitology

authors

Jenkins MC,O'Brien CN,Parker C

doi

10.1016/j.molbiopara.2019.111219

subject

Has Abstract

pub_date

2019-10-01 00:00:00

pages

111219

eissn

0166-6851

issn

1872-9428

pii

S0166-6851(19)30086-6

journal_volume

233

pub_type

杂志文章

在线工具

Excystation of Eimeria acervulina, E. maxima, and E. tenella differs in response to trypsin and chymotrypsin and the presence of reducing agents DTT and TCEP.