Platypus immunoglobulin M and the divergence of the two extant monotreme lineages

2003 ◽  
Vol 25 (1) ◽  
pp. 87 ◽  
Author(s):  
K Belov ◽  
L Hellman
Keyword(s):  
Phylogenetic Analysis ◽  
Amino Acid ◽  
Common Ancestor ◽  
Variable Region ◽  
Immunoglobulin M ◽  
Last Common Ancestor ◽  
Constant Region ◽  
Sequence Comparisons ◽  
Level Sequence ◽  
High Level

A full-length cDNA clone encoding the platypus (Ornithorynchus anatinus) immunoglobulin M (IgM) heavy chain was isolated from a spleen cDNA library using a short-beaked echidna (Tachyglossus aculeatus) IgM constant region (Cµ) probe. The isolation of platypus IgM shows that O. anatinus, like all other examined jawed vertebrates, express a classical IgM molecule. Amino acid sequence comparisons of the constant regions of IgM reveals a high level sequence conservation between O. anatinus and T. aculeatus sequences (87%), and only approximately 48% identity between O. anatinus and therian Cµ sequences. The variable region of this clone belongs to clan 3, supporting the view that this family is used preferentially, if not exclusively by O. anatinus, as opposed to the use of all three variable region clans by T. aculeatus. Phylogenetic analysis of Cµ sequences supports the traditional Theria hypothesis and suggests that the O. anatinus and T. aculeatus lineages separated from their last common ancestor approximately 21 million years ago.

scholarly journals Evolution of the Heme Peroxidases of Culicidae (Diptera)

2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Austin L. Hughes
Keyword(s):  
Amino Acid ◽  
Gene Duplication ◽  
Common Ancestor ◽  
Expression Patterns ◽  
Amino Acid Level ◽  
Recent Common Ancestor ◽  
Amino Acid Sequence Level ◽  
Most Recent Common Ancestor ◽  
High Level ◽  
Heme Peroxidases

Phylogenetic analysis of heme peroxidases (HPXs) of Culicidae and other insects revealed six highly conserved ancient HPX lineages, each of which originated by gene duplication prior to the most recent common ancestor (MRCA) of Hemimetabola and Holmetabola. In addition, culicid HPX7 and HPX12 arose by gene duplication after the MRCA of Culicidae and Drosophilidae, while HPX2 orthologs were not found in any other order analyzed except Diptera. Within Diptera, HPX2, HPX7, and HPX12 were relatively poorly conserved at the amino acid level in comparison to the six ancient lineages. The genome ofAnopheles gambiaeincluded genes ecoding five proteins (HPX10, HPX11, HPX13, HXP14, and HPX15) without ortholgs in other genomes analyzed. Overall, gene expression patterns did not seem to reflect phylogenetic relationships, but genes that evolved rapidly at the amino acid sequence level tended to have divergent expression patterns as well. The uniquely high level of duplication of HPXs inA. gambiaemay have played a role in coevolution with malaria parasites.

scholarly journals An early Cambrian polyp reveals an anemone-like ancestor for medusozoan cnidarians

2021 ◽  
Author(s):  
Yang Zhao ◽  
Luke Parry ◽  
Jakob Vinther ◽  
Frances S. Dunn ◽  
Yujing Li ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Fossil Record ◽  
Soft Tissues ◽  
Common Ancestor ◽  
Last Common Ancestor ◽  
Early Cambrian ◽  
Crown Group ◽  
Sessile Polyp ◽  
Animal Evolution ◽  
Chengjiang Biota

Extant cnidarians are a disparate phylum of non-bilaterians and their diploblastic body plan represents a key step in animal evolution. Anthozoans (anemones, corals) are benthic polyps, while adult medusozoans (jellyfishes) are dominantly pelagic medusae. A sessile polyp is present in both groups and is widely conceived as the ancestral form of their last common ancestor. However, the nature and anatomy of this ancestral polyp, particularly of medusozoans, are controversial, owing to the divergent body plans of both groups in the extant lineages and the rarity of medusozoan soft tissues in the fossil record. Here we redescribe the enigmatic Conicula striata Luo et Hu from the early Cambrian Chengjiang biota, south China, which has previously been interpreted as a polyp, lophophorate or deuterostome. We show that C. striata possessed features of both anthozoans and medusozoans. Its stalked polyp and fully encasing conical, annulated organic skeleton (periderm) are features of medusozoans. However, the gut is partitioned by ~28 mesenteries, and has a tubular pharynx, resembling anthozoans. Our phylogenetic analysis recovers C. striata as a stem medusozoan, indicating that the enormously diverse medusozoans were derived from an anemone-like ancestor, with the pharynx lost and number of mesenteries reduced prior to the origin of crown group Medusozoa.

Sequence and Phylogenetic Analysis of the Haemagglutinin Genes of H9N2 Avian Influenza Viruses Isolated from Commercial Chickens in Markazi Province, Iran

2018 ◽  
Vol 11 (3) ◽  
pp. 173-177
Author(s):  
Hamid Reza Saeidi ◽  
Alireza Homayounimehr ◽  
Seyed Davood Hosseini ◽  
Hossein Hosseini ◽  
Vaziri Hamidreza
Keyword(s):  
Phylogenetic Analysis ◽  
Amino Acid ◽  
Avian Influenza ◽  
Mammalian Species ◽  
Allantoic Fluid ◽  
Influenza Viruses ◽  
Avian Influenza Viruses ◽  
Sequence Comparisons ◽  
Relationship Of ◽  
Commercial Chickens

Avian influenza viruses of the H9N2 subtype have seriously affected the industry of the Middle East and Asian countries since the 1990s and are considered to be one of the potential candidates for the next human pandemic. In the present study, to determine the genetic relationship of Iranian viruses, the haemagglutinin (HA) genes from two isolates of H9N2 viruses from commercial chickens in Markazi province (central Iran) during 2013– 2014 were amplified and sequenced. Samples were collected and viruses were passed in embryonated hen eggs and virion RNA was extracted from allantoic fluid and reverse transcribed to synthesise cDNA. cDNA was amplified by PCR and the PCR product was purified with a purification kit. Purified fragments were sequenced from both directions. Finally, sequence analysis and phylogenetic studies were conducted by comparing each isolate with those of the available H9N2 strains at Gen Bank. All of the isolates possessed the same amino acid motif P-A-R-S-S-R/G-L at the HA cleavage site. Amino acid sequence comparisons of HA genes of two isolates showed 93.6% identity. Phylogenetic analysis revealed that all isolates belonged to the G1-like sublineage and one isolate showed some degree of homology with Pakistani isolates. Two isolates had leucine (L) at position 226 instead of glutamine (Q) which indicated the potential of binding to human-type receptors. The results of this study suggest that Iranian H9N2 viruses could infect mammalian species, including humans and have the potential to emerge as highly pathogenic influenza viruses in Iran.

scholarly journals Metaxin 3 is a Highly Conserved Vertebrate Protein Homologous to Mitochondrial Import Proteins and GSTs

2019 ◽  
Author(s):  
Kenneth W. Adolph
Keyword(s):  
Phylogenetic Analysis ◽  
Amino Acid ◽  
Common Ancestor ◽  
Protein Sequences ◽  
Amino Acid Sequences ◽  
Vertebrate Species ◽  
Mitochondrial Import ◽  
Alpha Helices ◽  
Thrombospondin 4 ◽  
Vertebrate Protein

ABSTRACTMetaxin 3 genes are shown to be widely conserved in vertebrates, including mammals, birds, fish, amphibians, and reptiles. Metaxin 3 genes, however, are not found in invertebrates, plants, and bacteria. The predicted metaxin 3 proteins were identified by their homology to the metaxin 3 proteins encoded by zebrafish and Xenopus cDNAs. Further evidence that they are metaxin proteins was provided by the presence of GST_N_Metaxin, GST_C_Metaxin, and Tom37 protein domains, and the absence of other major domains. Alignment of human metaxin 3 and human metaxin 1 predicted amino acid sequences showed 45% identities, while human metaxin 2 had 23% identities. These results indicate that metaxin 3 is a distinct metaxin. A wide variety of vertebrate species—including human, zebrafish, Xenopus, dog, shark, elephant, panda, and platypus—had the same genes adjacent to the metaxin 3 gene. In particular, the thrombospondin 4 gene (THBS4) is next to the metaxin 3 gene (MTX3). By comparison, the thrombospondin 3 gene (THBS3) is next to the metaxin 1 gene (MTX1). Phylogenetic analysis showed that metaxin 3, metaxin 1, and metaxin 2 protein sequences formed separate clusters, but with all three metaxins being derived from a common ancestor. Alpha-helices dominate the predicted secondary structures of metaxin 3 proteins. Little beta-strand is present. The pattern of 9 helical segments is also found for metaxins 1 and 2.

scholarly journals Glycosylation of a VH residue of a monoclonal antibody against alpha (1----6) dextran increases its affinity for antigen.

1988 ◽  
Vol 168 (3) ◽  
pp. 1099-1109 ◽  
Author(s):  
S C Wallick ◽  
E A Kabat ◽  
S L Morrison
Keyword(s):  
Monoclonal Antibody ◽  
Amino Acid ◽  
Amino Acid Sequence ◽  
Gene Transfection ◽  
Variable Region ◽  
Constant Region ◽  
Con A ◽  
Glycosylation Sites ◽  
Antigen Antibody

We have observed that antidextran hybridomas with potential N-linked glycosylation sites in VH have higher affinity for polymeric dextran and for isomaltoheptaose than those lacking potential glycosylation sites. In these studies we have used gene transfection and expression techniques to verify that the carbohydrate addition sites in VH were used. The carbohydrate of the VH region was accessible for binding by the lectin Con A. By ELISA analysis it was demonstrated that the aKa of the antibody for dextran was influenced by the presence of carbohydrate in VH, with the aglycosylated antibody having an aKa 15-fold lower than its untreated counterpart. The aKa for antigen of antibodies that contain carbohydrate only in their constant region was unaffected by lack of carbohydrate. Thus, not only the amino acid sequence of the variable region but also its carbohydrate moieties can determine the magnitude of the antigen-antibody interaction.

scholarly journals Peptidoglycan editing provides immunity to Acinetobacter baumannii during bacterial warfare

2020 ◽  
Vol 6 (30) ◽  
pp. eabb5614 ◽  
Author(s):  
Nguyen-Hung Le ◽  
Katharina Peters ◽  
Akbar Espaillat ◽  
Jessica R. Sheldon ◽  
Joe Gray ◽  
...  
Keyword(s):  
Amino Acid ◽  
Acinetobacter Baumannii ◽  
Common Ancestor ◽  
Phylogenetic Analyses ◽  
Acid Oxidase ◽  
Last Common Ancestor ◽  
Type Vi Secretion System ◽  
Amino Acid Oxidase ◽  
Type Vi Secretion ◽  
Human Enzyme

Peptidoglycan (PG) is essential in most bacteria. Thus, it is often targeted by various assaults, including interbacterial attacks via the type VI secretion system (T6SS). Here, we report that the Gram-negative bacterium Acinetobacter baumannii strain ATCC 17978 produces, secretes, and incorporates the noncanonical d-amino acid d-lysine into its PG during stationary phase. We show that PG editing increases the competitiveness of A. baumannii during bacterial warfare by providing immunity against peptidoglycan-targeting T6SS effectors from various bacterial competitors. In contrast, we found that d-Lys production is detrimental to pathogenesis due, at least in part, to the activity of the human enzyme d-amino acid oxidase (DAO), which degrades d-Lys producing H2O2 toxic to bacteria. Phylogenetic analyses indicate that the last common ancestor of A. baumannii had the ability to produce d-Lys. However, this trait was independently lost multiple times, likely reflecting the evolution of A. baumannii as a human pathogen.

scholarly journals Peptidoglycan editing provides immunity to Acinetobacter baumannii during bacterial warfare

2020 ◽  
Author(s):  
Nguyen-Hung Le ◽  
Katharina Peters ◽  
Akbar Espaillat ◽  
Jessica R. Sheldon ◽  
Joe Gray ◽  
...  
Keyword(s):  
Amino Acid ◽  
Acinetobacter Baumannii ◽  
Common Ancestor ◽  
Phylogenetic Analyses ◽  
Acid Oxidase ◽  
Last Common Ancestor ◽  
Type Vi Secretion System ◽  
Amino Acid Oxidase ◽  
Type Vi Secretion ◽  
Human Enzyme

AbstractPeptidoglycan (PG) is essential in most bacteria. Thus, it is often targeted by various assaults, including the host immune response, antibiotic treatment and interbacterial attacks via the type VI secretion system (T6SS). Here, we report that the Gram-negative bacterium Acinetobacter baumannii strain ATCC 17978 produces, secretes and incorporates the non-canonical D-amino acid D-Lysine into its PG during stationary phase. We show that PG editing increases the competitiveness of A. baumannii during bacterial warfare by providing immunity against peptidoglycan-targeting T6SS effectors from various bacterial competitors. We propose that PG editing has evolved as an effective strategy for bacteria to overcome T6SS attacks. In contrast, we found that D-Lys production is detrimental to pathogenesis due, at least in part, to the activity of the human enzyme D-amino acid oxidase (DAO), which degrades D-Lys producing H2O2 toxic to bacteria. Phylogenetic analyses indicate that the last common ancestor of A. baumannii possessed the ability to produce D-Lys. However, this trait was independently lost multiple times, likely reflecting the evolution of A. baumannii as a human pathogen.One sentence summaryAcinetobacter baumannii attains immunity against nonkin competitors during T6SS warfare by incorporating D-Lysine into its peptidoglycan.

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