Author's posts
Jun 10
The role of purifying selection in the origin and maintenance of complex function
Stud Hist Philos Sci. 2021 Apr 11;87:125-135. doi: 10.1016/j.shpsa.2021.03.005. Online ahead of print. ABSTRACT Fitness contribution alone should not be the criterion of ‘function’ in molecular biology and genomics. Disagreement over the use of ‘function’ in molecular biology and genomics is still with us, almost eight years after publicity surrounding the Encyclopedia of DNA Elements …
Jun 10
‘Species’ without species
Stud Hist Philos Sci. 2021 Apr 1;87:72-80. doi: 10.1016/j.shpsa.2021.03.006. Online ahead of print. ABSTRACT Biological science uses multiple species concepts. Order can be brought to this diversity if we recognize two key features. First, any given species concept is likely to have a patchwork structure, generated by repeated application of the concept to new domains. …
Jun 05
q-PCR-based assay for the toxic dinoflagellate Karenia selliformis monitoring along the Tunisian coasts
Karenia selliformis is a marine dinoflagellate responsible for fish-kill events. Its presence has been reported along the Tunisian coasts (south-eastern Mediterranean Sea) since the 1990s. In the present study, a quantitative-PCR assay, based on the internal transcribed spacer (ITS) molecular marker, was developed to detect and quantify K. selliformis in environmental bivalve mollusk samples and in seawater samples. The assay was optimized, and its specificity was confirmed using…
May 28
Gamma4: a genetically versatile Gammaproteobacterial nifH phylotype that is widely distributed in the North Pacific Ocean
Despite the increasing reports of non-cyanobacterial diazotrophs (NCDs) in pelagic waters, only one NCD (GammaA) has been relatively well described, whose genome and physiology are still unclear. Here we present a comprehensive analysis of the biogeography and ecophysiology of a widely distributed NCD, Gamma4. Gamma4 was the most abundant Gammaproteobacterial NCD along transects across the subtropical North Pacific. Using quantitative PCR, Gamma4 was detectable throughout the surface waters of…
May 25
Re-examination of two diatom reference genomes using long-read sequencing
BMC Genomics. 2021 May 24;22(1):379. doi: 10.1186/s12864-021-07666-3. ABSTRACT BACKGROUND: The marine diatoms Thalassiosira pseudonana and Phaeodactylum tricornutum are valuable model organisms for exploring the evolution, diversity and ecology of this important algal group. Their reference genomes, published in 2004 and 2008, respectively, were the product of traditional Sanger sequencing. In the case of T. pseudonana, …
May 20
Analysis of diverse eukaryotes suggests the existence of an ancestral mitochondrial apparatus derived from the bacterial type II secretion system
Nat Commun. 2021 May 19;12(1):2947. doi: 10.1038/s41467-021-23046-7. ABSTRACT The type 2 secretion system (T2SS) is present in some Gram-negative eubacteria and used to secrete proteins across the outer membrane. Here we report that certain representative heteroloboseans, jakobids, malawimonads and hemimastigotes unexpectedly possess homologues of core T2SS components. We show that at least some of them …
May 19
Identifying biases and their potential solutions in human microbiome studies
Microbiome. 2021 May 18;9(1):113. doi: 10.1186/s40168-021-01059-0. ABSTRACT Advances in DNA sequencing technology have vastly improved the ability of researchers to explore the microbial inhabitants of the human body. Unfortunately, while these studies have uncovered the importance of these microbial communities to our health, they often do not result in similar findings. One possible reason for …
May 19
Treasurer’s Report for Financial Year (FY) 2019
Mol Biol Evol. 2021 May 3:msab012. doi: 10.1093/molbev/msab012. Online ahead of print. NO ABSTRACT PMID:34009329 | DOI:10.1093/molbev/msab012
May 08
Genomic variation of an endosymbiotic dinoflagellate (Symbiodinium ‘fitti’) among closely related coral hosts
Mutualisms where hosts are coupled metabolically to their symbionts often exhibit high partner fidelity. Most reef-building coral species form obligate symbioses with a specific species of photosymbionts, dinoflagellates in the family Symbiodiniaceae, despite needing to acquire symbionts early in their development from environmental sources. Three Caribbean acroporids (Acropora palmata, A. cervicornis, and their F1 hybrid) are sympatric across much of their range, but often occupy different…
May 04
Maricaulis alexandrii sp. nov., a novel active bioflocculants-bearing and dimorphic prosthecate bacterium isolated from marine phycosphere
An aerobic, Gram-stain-negative, straight or curved rods and dimorphic prosthecate bacterium designated as strain LZ-16-1^(T) was isolated from phycosphere microbiota of routinely laboratory-cultured and highly-toxic marine dinoflagellate Alexandrium catenella LZT09. Strain LZ-16-1^(T) produces active bioflocculanting exopolysaccharides (EPS). Cells were dimorphic with non-motile prostheca, or non-stalked and motile by a single polar flagellum. Growth occurred at 10-40 °C, pH 5-9 and 1-8% (w/v)…