Improved thermostability of the North American firefly luciferase: saturation mutagenesis at position 354

We have used random chemical mutagenesis and a simple genetic screen to generate and isolate a thermostable mutant of luciferase from the North American firefly (Photinus pyralis). A single G-to-A transition mutation, resulting in the substitution of a glutamate for a lysine residue at position 354 in the protein sequence, was shown to be responsible for this enhanced thermostability. Replacement of Glu-354 with all possible amino acid residues was achieved using directed mutagenesis, and produced mutant enzymes with a range of thermostabilities. The mutations E354K and E354R conferred the largest increases in thermostability, suggesting that side-chain size and hydrophobicity, as well as charge, may also be important contributors to the overall thermostability of the polypeptide chain at this position. Unusually for such mutations, biochemical studies suggest that this position is on the surface of the protein and exposed to solvent.

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Firefly genomes illuminate parallel origins of bioluminescence in beetles

10.1101/237586 ◽

2017 ◽

Cited By ~ 1

Author(s):

Timothy R. Fallon ◽

Sarah E. Lower ◽

Ching-Ho Chang ◽

Manabu Bessho-Uehara ◽

Gavin J. Martin ◽

...

Keyword(s):

Firefly Luciferase ◽

Chemical Defenses ◽

Photinus Pyralis ◽

Click Beetles ◽

Origin And Evolution ◽

The North ◽

Click Beetle ◽

Light Organs ◽

The Caribbean ◽

Shed Light

AbstractFireflies and their fascinating luminous courtships have inspired centuries of scientific study. Today firefly luciferase is widely used in biotechnology, but the evolutionary origin of their bioluminescence remains unclear. To shed light on this long-standing question, we sequenced the genomes of two firefly species that diverged over 100 million-years-ago: the North AmericanPhotinus pyralisand JapaneseAquatica lateralis.We also sequenced the genome of a related click-beetle, the CaribbeanIgnelater luminosus,with bioluminescent biochemistry near-identical to fireflies, but anatomically unique light organs, suggesting the intriguing but contentious hypothesis of parallel gains of bioluminescence. Our analyses support two independent gains of bioluminescence between fireflies and click-beetles, and provide new insights into the genes, chemical defenses, and symbionts that evolved alongside their luminous lifestyle.One Sentence Summary:Comparative analyses of the first linkage-group-resolution genomes of fireflies and related bioluminescent beetles address long-standing questions of the origin and evolution of bioluminescence and its associated traits.

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N.M.R. studies on myelin basic protein. I. 13C spectra in aqueous solutions

Australian Journal of Chemistry ◽

10.1071/ch9782367 ◽

1978 ◽

Vol 31 (11) ◽

pp. 2367 ◽

Cited By ~ 20

Author(s):

BE Chapman ◽

WJ Moore

Keyword(s):

Myelin Basic Protein ◽

Basic Protein ◽

Polypeptide Chain ◽

Random Coil ◽

Side Chain ◽

Amino Acid Residues ◽

Native Protein ◽

Denatured Protein ◽

Coil Structure ◽

Random Coil Structure

Carbon-13 n.m.r, spectra have been obtained for bovine myelin basic protein at pD 4.4 in D2O and in 6 M guanidine deuterochloride solutions. Chemical-shift differences between resonances from some amino acid residues are interpreted in terms of structured regions in the polypeptide chain of the native protein, whereas the denatured protein displays the spectrum expected for an essentially random coil. Measurements of T1 and n.O.e. provide quantitative data on the dynamics of the backbone and side-chain carbons, and give support to the conclusion that the native protein does not have a random-coil structure.

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Firefly genomes illuminate parallel origins of bioluminescence in beetles

eLife ◽

10.7554/elife.36495 ◽

2018 ◽

Vol 7 ◽

Cited By ~ 44

Author(s):

Timothy R Fallon ◽

Sarah E Lower ◽

Ching-Ho Chang ◽

Manabu Bessho-Uehara ◽

Gavin J Martin ◽

...

Keyword(s):

Firefly Luciferase ◽

Chemical Defenses ◽

Photinus Pyralis ◽

Click Beetles ◽

The North ◽

Click Beetle ◽

Light Organs ◽

The Caribbean ◽

Shed Light ◽

Standing Question

Fireflies and their luminous courtships have inspired centuries of scientific study. Today firefly luciferase is widely used in biotechnology, but the evolutionary origin of bioluminescence within beetles remains unclear. To shed light on this long-standing question, we sequenced the genomes of two firefly species that diverged over 100 million-years-ago: the North American Photinus pyralis and Japanese Aquatica lateralis. To compare bioluminescent origins, we also sequenced the genome of a related click beetle, the Caribbean Ignelater luminosus, with bioluminescent biochemistry near-identical to fireflies, but anatomically unique light organs, suggesting the intriguing hypothesis of parallel gains of bioluminescence. Our analyses support independent gains of bioluminescence in fireflies and click beetles, and provide new insights into the genes, chemical defenses, and symbionts that evolved alongside their luminous lifestyle.

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On the inference of a southern origin of the North American firefly Photinus pyralis

10.1101/851139 ◽

2019 ◽

Author(s):

Ana Catalán ◽

Sebastian Höhna ◽

Sarah E. Lower ◽

Pablo Duchen

Keyword(s):

North American ◽

Eastern Coast ◽

Ecological Niches ◽

Photinus Pyralis ◽

The North ◽

Ideal System ◽

Wide Range ◽

North Eastern ◽

Demographic Inference ◽

Population Demographic

AbstractThe firefly Photinus pyralis inhabits a wide range of latitudinal and ecological niches, with populations living from temperate to tropical habitats. Its ample geographic distribution makes this species an ideal system for the study of local adaptation and demographic inference of wild populations. Therefore, in this study we modelled and inferred different demographic scenarios for North American populations of P. pyralis, collected from Texas to New Jersey. To do this, we used a combination of ABC techniques (for multi-population/colonization analyses), and likelihood inference (dadi) for single-population demographic inference, which proved useful with our RAD data.We uncovered that the most ancestral North American population lays in Texas, which further colonized the Central region of the US and more recently the North Eastern coast. Our study confidently rejects a demographic scenario where the North Eastern populations colonized more southern populations until reaching Texas. Our results suggest that P. pyralis originated in Central- or South America, followed by migration events that populated northern latitudes. Finally, modelling the demographic history of North American P. pyralis serves as a null model of nucleotide diversity patterns, which will inform future studies of adaptation, not only in P. pyralis, but also in other North American taxa.

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