Hannu Myllykallio

The structure of an archaeal homodimeric ligase which has RNA circularization activity (2008)

Brooks, Mark Adrian, Meslet-Cladiére, Laurence, Graille, Marc, Kuhn, Joëlle, Blondeau, Karine, Myllykallio, Hannu, ...

The genome of Pyrococcus abyssi contains two open reading frames encoding proteins which had been previously predicted to be DNA ligases, Pab2002 and Pab1020. We show that while the former is indeed...

The heterodimeric primase from the Euryarchaea Pyrococcus abyssi: a multifunctional enzyme for initiation and repair ? (2007)

LE BRETON, Magali, HENNEKE, Ghislaine, NORAIS, Cédric, FLAMENT, Didier, MYLLYKALLIO, Hannu, QUERELLOU, Joel, ...

We report the characterization of the DNA primase complex of the hyperthermophilic archaeon Pyrococcus abyssi (Pab). The Pab DNA primase complex is composed of two proteins, Pabp41 and Pabp46,...

A novel proteomic approach identifies new interaction partners for proliferating cell nuclear antigen (2007)

MESIET CLADIERE, L, NORAIS, Cédric, KUHN, Joelle, BRIFFOTAUX, Julien, SLOOSTRA, Jerry W., FERRARI, Elena, ...

During DNA replication and repair, many proteins bind to and dissociate in a highly specific and ordered manner from proliferating cell nuclear antigen (PCNA). We describe a combined approach of in...

Genetic and Physical Mapping of DNA Replication Origins in Haloferax volcanii (2007)

Cédric Norais, Michelle Hawkins, Amber L. Hartman, Jonathan A. Eisen, Hannu Myllykallio, Thorsten Allers

The halophilic archaeon Haloferax volcanii has a multireplicon genome, consisting of a main chromosome, three secondary chromosomes, and a plasmid. Genes for the initiator protein Cdc6/Orc1, which...

Genetic and physical mapping of DNA replication origins in Haloferax volcanii (2007)

Cédric Norais, Michelle Hawkins, Amber L Hartman, Jonathan A. Eisen, Hannu Myllykallio, Thorsten Allers

The halophilic archaeon Haloferax volcanii has a multi-replicon genome, consisting of a main chromosome, three secondary chromosomes, and a plasmid. Genes for the initiator protein Cdc6/Orc1, which...

Identification of a novel gene encoding a flavin-dependent tRNA:m5U methyltransferase in bacteria--evolutionary implications (2005)

Urbonavicius, Jaunius, Skouloubris, Stéphane, Myllykallio, Hannu, Grosjean, Henri

Formation of 5-methyluridine (ribothymidine) at position 54 of the T-psi loop of tRNA is catalyzed by site-specific tRNA methyltransferases (tRNA:m5U-54 MTase). In all Eukarya and many Gram-negative...

The membrane-attached electron carrier cytochrome cy from Rhodobacter sphaeroides is functional in respiratory but not in photosynthetic electron transfer

Myllykallio, Hannu, Zannoni, Davide, Daldal, Fevzi

Rhodobacter species are useful model organisms for studying the structure and function of c type cytochromes (Cyt c), which are ubiquitous electron carriers with essential functions in cellular...

In vivo interactions of archaeal Cdc6/Orc1 and minichromosome maintenance proteins with the replication origin

Matsunaga, Fujihiko, Forterre, Patrick, Ishino, Yoshizumi, Myllykallio, Hannu

Although genome analyses have suggested parallels between archaeal and eukaryotic replication systems, little is known about the DNA replication mechanism in Archaea. By two-dimensional gel...

Mobile Cytochrome c2 and Membrane-Anchored Cytochrome cy Are Both Efficient Electron Donors to the cbb3- and aa3-Type Cytochrome c Oxidases during Respiratory Growth of Rhodobacter sphaeroides

Daldal, Fevzi, Mandaci, Sevnur, Winterstein, Christine, Myllykallio, Hannu, Duyck, Kristen, Zannoni, Davide

We have recently established that the facultative phototrophic bacterium Rhodobacter sphaeroides, like the closely related Rhodobacter capsulatus species, contains both the previously characterized...

Physiological Responses of the Hyperthermophilic Archaeon “Pyrococcus abyssi” to DNA Damage Caused by Ionizing Radiation

Jolivet, Edmond, Matsunaga, Fujihiko, Ishino, Yoshizumi, Forterre, Patrick, Prieur, Daniel, Myllykallio, Hannu

The mechanisms by which hyperthermophilic Archaea, such as “Pyrococcus abyssi” and Pyrococcus furiosus, survive high doses of ionizing gamma irradiation are not thoroughly elucidated. Following...

Functional evidence for active site location of tetrameric thymidylate synthase X at the interphase of three monomers

Leduc, Damien, Graziani, Sébastien, Lipowski, Gerard, Marchand, Christophe, Le Maréchal, Pierre, Liebl, Ursula, ...

Little is known about the catalytic mechanism of the recently discovered ThyX family of flavin-dependent thymidylate synthases that are required for thymidylate (deoxythymidine 5′-monophosphate)...

Identification of a novel gene encoding a flavin-dependent tRNA:m5U methyltransferase in bacteria—evolutionary implications

Urbonavičius, Jaunius, Skouloubris, Stéphane, Myllykallio, Hannu, Grosjean, Henri

Formation of 5-methyluridine (ribothymidine) at position 54 of the T-psi loop of tRNA is catalyzed by site-specific tRNA methyltransferases (tRNA:m5U-54 MTase). In all Eukarya and many Gram-negative...

Identification of short 'eukaryotic' Okazaki fragments synthesized from a prokaryotic replication origin

Matsunaga, Fujihiko, Norais, Cédric, Forterre, Patrick, Myllykallio, Hannu

Although archaeal genomes encode proteins similar to eukaryotic replication factors, the hyperthermophilic archaeon Pyrococcus abyssi replicates its circular chromosome at a high rate from a single...

Function and Evolution of Plasmid-Borne Genes for Pyrimidine Biosynthesis in Borrelia spp.

Zhong, Jianmin, Skouloubris, Stephane, Dai, Qiyuan, Myllykallio, Hannu, Barbour, Alan G.

The thyX gene for thymidylate synthase of the Lyme borreliosis (LB) agent Borrelia burgdorferi is located in a 54-kb linear plasmid. In the present study, we identified an orthologous thymidylate...

The membrane-attached electron carrier cytochrome cy from Rhodobacter sphaeroides is functional in respiratory but not in photosynthetic electron transfer

Myllykallio, Hannu, Zannoni, Davide, Daldal, Fevzi

Rhodobacter species are useful model organisms for studying the structure and function of c type cytochromes (Cyt c), which are ubiquitous electron carriers with essential functions in cellular...

In vivo interactions of archaeal Cdc6/Orc1 and minichromosome maintenance proteins with the replication origin

Matsunaga, Fujihiko, Forterre, Patrick, Ishino, Yoshizumi, Myllykallio, Hannu

Although genome analyses have suggested parallels between archaeal and eukaryotic replication systems, little is known about the DNA replication mechanism in Archaea. By two-dimensional gel...

Mobile Cytochrome c2 and Membrane-Anchored Cytochrome cy Are Both Efficient Electron Donors to the cbb3- and aa3-Type Cytochrome c Oxidases during Respiratory Growth of Rhodobacter sphaeroides

Daldal, Fevzi, Mandaci, Sevnur, Winterstein, Christine, Myllykallio, Hannu, Duyck, Kristen, Zannoni, Davide

We have recently established that the facultative phototrophic bacterium Rhodobacter sphaeroides, like the closely related Rhodobacter capsulatus species, contains both the previously characterized...

Physiological Responses of the Hyperthermophilic Archaeon “Pyrococcus abyssi” to DNA Damage Caused by Ionizing Radiation

Jolivet, Edmond, Matsunaga, Fujihiko, Ishino, Yoshizumi, Forterre, Patrick, Prieur, Daniel, Myllykallio, Hannu

The mechanisms by which hyperthermophilic Archaea, such as “Pyrococcus abyssi” and Pyrococcus furiosus, survive high doses of ionizing gamma irradiation are not thoroughly elucidated. Following...

Functional evidence for active site location of tetrameric thymidylate synthase X at the interphase of three monomers

Leduc, Damien, Graziani, Sébastien, Lipowski, Gerard, Marchand, Christophe, Le Maréchal, Pierre, Liebl, Ursula, ...

Little is known about the catalytic mechanism of the recently discovered ThyX family of flavin-dependent thymidylate synthases that are required for thymidylate (deoxythymidine 5′-monophosphate)...

Identification of a novel gene encoding a flavin-dependent tRNA:m5U methyltransferase in bacteria—evolutionary implications

Urbonavičius, Jaunius, Skouloubris, Stéphane, Myllykallio, Hannu, Grosjean, Henri

Formation of 5-methyluridine (ribothymidine) at position 54 of the T-psi loop of tRNA is catalyzed by site-specific tRNA methyltransferases (tRNA:m5U-54 MTase). In all Eukarya and many Gram-negative...

Identification of short 'eukaryotic' Okazaki fragments synthesized from a prokaryotic replication origin

Matsunaga, Fujihiko, Norais, Cédric, Forterre, Patrick, Myllykallio, Hannu

Although archaeal genomes encode proteins similar to eukaryotic replication factors, the hyperthermophilic archaeon Pyrococcus abyssi replicates its circular chromosome at a high rate from a single...

Function and Evolution of Plasmid-Borne Genes for Pyrimidine Biosynthesis in Borrelia spp.

Zhong, Jianmin, Skouloubris, Stephane, Dai, Qiyuan, Myllykallio, Hannu, Barbour, Alan G.

The thyX gene for thymidylate synthase of the Lyme borreliosis (LB) agent Borrelia burgdorferi is located in a 54-kb linear plasmid. In the present study, we identified an orthologous thymidylate...

Genetic and Physical Mapping of DNA Replication Origins in Haloferax volcanii

Norais, Cédric, Hawkins, Michelle, Hartman, Amber L, Eisen, Jonathan A, Myllykallio, Hannu, Allers, Thorsten

The halophilic archaeon Haloferax volcanii has a multireplicon genome, consisting of a main chromosome, three secondary chromosomes, and a plasmid. Genes for the initiator protein Cdc6/Orc1, which...

Flavin-Dependent Thymidylate Synthase ThyX Activity: Implications for the Folate Cycle in Bacteria▿ †

Leduc, Damien, Escartin, Frédéric, Nijhout, H. Frederik, Reed, Michael C., Liebl, Ursula, Skouloubris, Stéphane, ...

Although flavin-dependent ThyX proteins show thymidylate synthase activity in vitro and functionally complement thyA defects in heterologous systems, direct proof of their cellular functions is...

Functional Analysis of the Mycobacterium tuberculosis FAD-Dependent Thymidylate Synthase, ThyX, Reveals New Amino Acid Residues Contributing to an Extended ThyX Motif▿ †

Ulmer, Jonathan E., Boum, Yap, Thouvenel, Christopher D., Myllykallio, Hannu, Sibley, Carol Hopkins

A novel FAD-dependent thymidylate synthase, ThyX, is present in a variety of eubacteria and archaea, including the mycobacteria. A short motif found in all thyX genes, RHRX7-8S, has been identified....

Flavin-dependent thymidylate synthase X limits chromosomal DNA replication

Escartin, Frédéric, Skouloubris, Stéphane, Liebl, Ursula, Myllykallio, Hannu

We have investigated the hitherto unexplored possibility that differences in the catalytic efficiencies of thymidylate synthases ThyX and ThyA, enzymes that produce the essential DNA precursor dTMP,...

Crystallization and preliminary X-ray analysis of a RecB-family nuclease from the archaeon Pyrococcus abyssi

Ren, Bin, Kuhn, Joëlle, Meslet-Cladiere, Laurence, Myllykallio, Hannu, Ladenstein, Rudolf

A RecB-like nuclease from the archaeon Pyrococcus abyssi was expressed, purified and crystallized. The crystals belong to the orthorhombic space group C2221 with a = 81.5, b = 159.8, c = 100.8 Å,...

The structure of an archaeal homodimeric ligase which has RNA circularization activity

Brooks, Mark Adrian, Meslet-Cladiére, Laurence, Graille, Marc, Kuhn, Joëlle, Blondeau, Karine, Myllykallio, Hannu, ...

The genome of Pyrococcus abyssi contains two open reading frames encoding proteins which had been previously predicted to be DNA ligases, Pab2002 and Pab1020. We show that while the former is indeed...