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Giardia duodenalis, formerly known as Giardia lamblia, is an important zoonotic protozoan parasite. It mainly infects the intestines of humans, dogs, cats and domestic animals, causing diarrhea, abdominal pain, indigestion and weight loss. At present, all the clinical drugs for the treatment of Giardia have problems such as side effects and drug resistance to varying degrees, and the development of new drugs for the treatment of Giardia is still a hot issue. There is growing interest in using probiotics as an anti-intestinal parasite strategy. The present study aimed to assess the effect of supernatants of Bifidobacterium Animalis Subsp. lactis BB-12 on giardia the growth of giardia trophozoites. In this study, the Bifidobacterium animalis subsp. lactis BB-12 were cultured in BBL liquid medium, and the effects of the supernatants on the growth and adhesion of trophozoites of Giardia were observed. The results showed that the growth of Giardia flagellate was significantly inhibited by the supernatant. The influence of the supernatant on the morphology of the trophozoites was observed by microscope, and it was found that the surface of the trophozoites was uneven, the shape was atrophied, the surface cell membrane was broken to some extent, and the contents were spilt. In summary, the results of this study suggest that the fresh-cultured supernatants of the probiotic Bifidobacterium Animalis subsp. lactis BB-12 have anti-Giardia effects.

Copepoda is a large and diverse group of crustaceans, which is widely distributed worldwide. It encompasses roughly 9 orders, whose phylogeny remains unresolved. We sequenced the complete mitochondrial genome (mitogenome) of Sinergasilus major (Markevich, 1940) and used it to explore the phylogeny and mitogenomic evolution of Copepoda. The mitogenome of S. major (14,588 bp) encodes the standard 37 genes as well as a putative control region, and molecular features are highly conserved compared to other Copepoda mitogenomes. Comparative analyses indicated that the nad2 gene has relatively high nucleotide diversity and evolutionary rate, as well as the largest amount of phylogenetic information. These results indicate that nad2 may be a better marker to investigate phylogenetic relationships among closely related species in Copepoda than the commonly used cox1 gene. The sister-group relationship of Siphonostomatoida and Cyclopoida was recovered with strong support in our study. The only topological ambiguity was found within Cyclopoida, which might be caused by the rapid evolution and sparse taxon sampling of this lineage. More taxa and genes should be used to reconstruct the Copepoda phylogeny in the future. [ABSTRACT FROM AUTHOR]

In this paper, we present transcriptome data for Balantidium ctenopharyngodoni Chen, 1955 collected from the hindgut of grass carp (Ctenopharyngodon idella). We evaluated sequence quality and de novo assembled a preliminary transcriptome, including 43.3 megabits and 119,141 transcripts. Then we obtained a final transcriptome, including 17.7 megabits and 35,560 transcripts, by removing contaminative and redundant sequences. Phylogenomic analysis based on a supermatrix with 132 genes comprising 53,873 amino acid residues and phylogenetic analysis based on SSU rDNA of 27 species were carried out herein to reveal the evolutionary relationships among six ciliate groups: Colpodea, Oligohymenophorea, Litostomatea, Spirotrichea, Heterotrichea and Protocruziida. The topologies of both phylogenomic and phylogenetic trees are discussed in this paper. In addition, our results suggest that single-cell sequencing is a sound method of obtaining sufficient omics data for phylogenomic analysis, which is a good choice for uncultivable ciliates. The transcriptome data for Balantidium ctenopharyngodoni are the first omics data within the subclass Trichostomatia, and provide a good basis for ciliate phylogenomic analysis, as well as related omics analysis.

N-Acetylneuraminic acid lyase (NAL, E.C. number 4.1.3.3) is a Class I aldolase that catalyzes the reversible aldol cleavage of N-acetylneuraminic acid (Neu5Ac) from pyruvate and N-acetyl-D-mannosamine (ManNAc). Due to the equilibrium favoring Neu5Ac cleavage, the enzyme catalyzes the rate-limiting step of two biocatalytic reactions producing Neu5Ac in industry. We report the biochemical characterization of a novel NAL from a 'GRAS' (General recognized as safe) strain C. glutamicum ATCC 13032 (CgNal). Compared to all previously reported NALs, CgNal exhibited the lowest kcat/Km value for Neu5Ac and highest kcat/Km values for ManNAc and pyruvate, which makes CgNal favor Neu5Ac synthesis the most. The recombinant CgNal reached the highest expression level (480 mg/L culture), and the highest reported yield of Neu5Ac was achieved (194 g/L, 0.63 M). All these unique properties make CgNal a promising biocatalyst for industrial Neu5Ac biosynthesis. Additionally, although showing the best Neu5Ac synthesis activity among the NAL family, CgNal is more related to dihydrodipicolinate synthase (DHDPS) by phylogenetic analysis. The activities of CgNal towards both NAL's and DHDPS' substrates are fairly high, which indicates CgNal a bi-functional enzyme. The sequence analysis suggests that CgNal might have adopted a unique set of residues for substrates recognition. [ABSTRACT FROM AUTHOR]