Unveiling the multifaceted landscape of N-glycosylation in antibody variable domains: Insights and implications.

N-glycosylation at the antibody variable domain has emerged as an important modification influencing antibody function. Despite its significance, information regarding its role and regulation remains limited. To address this gap, we comprehensively explored antibody structures housing N-glycosylation within the Protein Data Bank, yielding fresh insights into this intricate landscape. Our findings revealed that among 208 structures, N-glycosylation was more prevalent in human and mouse antibodies containing IGHV1-8 and IGHV2-2 germline genes, respectively. Moreover, our research highlights the potential for somatic hypermutation to introduce N-glycosylation sites by substituting polar residues (Ser or Thr) in germline variable genes with asparagine. Notably, our study underscores the prevalence of N-glycosylation in antiviral antibodies, especially anti-HIV. Besides antigen-antibody interaction, our findings suggest that N-glycosylation may impact antibody specificity, affinity, and avidity by influencing Fab dimer formation and complementary-determining region orientation. We also identified different glycan structures in HIV and SARS-CoV-2 antibody proteomic datasets, highlighting disparities from the N-glycan structures between PDB antibodies and biological repertoires further highlighting the complexity of N-glycosylation patterns. Our findings significantly enrich our understanding of the N-glycosylation's multifaceted characteristics within the antibody variable domain. Additionally, they underscore the pressing imperative for a more comprehensive characterization of its impact on antibody function.

First complete mitochondrial genome for any anostomid fish: Leporinus piavussu, a recently described piracema species.

The first complete mitochondrial genome for the Anostomidae fish family has been announced. Piracema fishes are the potamodromous migratory species from South America, which undergo lengthy and dramatic yearly reproductive upstream runs. The piracema species Leporinus piavussu has recently been described after a long misidentification history. Its mitogenome, assembled using NGS data and Sanger sequencing, consists in a 16,682 bp circular molecule (GenBank accession number KM886569). The exact sequence and position of 37 mitochondrial genes and the control region is established. A possible case of heteroplasmy was found with NGS and corroborated by Sanger sequencing. These results will positively contribute to the debate about this group's taxonomy, evolution and conservation.