Cystoisospora sp.

Tokiwa, Toshihiro, Ohnuki, Ai, Kubota, Rie, Tamukai, Kenichi & Ike, Kazunori, 2018, Morphological and molecular characterization of Cystoisospora sp. from Asian small-clawed otters Aonyx cinereus, International Journal for Parasitology: Parasites and Wildlife 7 (3), pp. 268-273 : 270

3.2. Sequence analyses of Cystoisospora sp. from Asian small-clawed otters

A 1423-bp sequence of the 18S gene obtained from the three otters was identical in each otter and was deposited in the DDBJ database under accession no. LC377842. Sequence comparisons revealed that the present sequence from otters shared the highest identity (99.9%) for C. ohioensis (1422/1423, AY618555; 1421/1423, KT1843651, KT184359, KT184366) and C. suis (1421/1423, KF854252, KF854251). Similarities of 99.8% for C. belli (1420/1423, U94787, JX025649, AB268326, DQ060659, DQ060661), 99.6% for C. canis (1417/1423, KT184368), 99.4% for C. timoni (1415/1423, AY279205, EU200732) and C. orlovi (1414/1423, AY365026), and 99.2% for C. felis (1412/1423, KT134364) and C. canis (1412/1423, KT184362, KT184363, TK184360) were also noted. Sequence identity with the near complete 18S sequence of C. rivolta (AY618554) was 81.1% (1154/1447); however, this low similarity was thought to be due to incorrect registration of the sequence because high similarities (> 99%) were observed with the red yeast Rhodosporidium spp. The partial 18S sequence showed 100% identity (401/401) with that of C. rivolta (KT184367) and was identical to those of C. canis (KT184360, KT184362, KT184368), C. ohioensis (KT184351, KT184359, KT184366), C. suis (KF854252, KF854251), C. belli (U94787, JX025649, AB268326, DQ060659, DQ060661), and C. timoni (EU200792, AY279205).

An 847-bp sequence of the cox1 gene obtained from three otters was identical in each otter and deposited in the DDBJ database under accession no. LC377843. Sequence comparisons using BLAST revealed that the new sequence from otters was completely identical to that from C. rivolta (KT184383) and showed 99.8% (845/847) similarity to C. ohioensis (KT184384), 98.7% (836/847) similarity to C. canis (KT184385), and 98.4% (814/827) similarity to C. felis (KT184386). Table 1 shows the multiple alignment of cox1 sequences from 5 Cystoisospora species and the present species. A single nonsynonymous substitution occurred in between the present species and C. ohioensis (362: Ile to Leu), C. canis , and C. felis (371: Ile to Leu), and 2 nonsynonymous substitutions (362: Ile to Leu, 374: Leu to Ile) occurred in C. suis .