Origin of marine planktonic cyanobacteria

Marine planktonic cyanobacteria contributed to the widespread oxygenation of the oceans towards the end of the Pre-Cambrian and their evolutionary origin represents a key transition in the geochemical evolution of the Earth surface. Little is known, however, about the evolutionary events that led to the appearance of marine planktonic cyanobacteria. I present here phylogenomic (135 proteins and two ribosomal RNAs), Bayesian relaxed molecular clock (18 proteins, SSU and LSU) and Bayesian stochastic character mapping analyses from 131 cyanobacteria genomes with the aim to unravel key evolutionary steps involved in the origin of marine planktonic cyanobacteria. While filamentous cell types evolved early on at around 2,600–2,300 Mya and likely dominated microbial mats in benthic environments for most of the Proterozoic (2,500–542 Mya), marine planktonic cyanobacteria evolved towards the end of the Proterozoic and early Phanerozoic. Crown groups of modern terrestrial and/or benthic coastal cyanobacteria appeared during the late Paleoproterozoic to early Mesoproterozoic. Decrease in cell diameter and loss of filamentous forms contributed to the evolution of unicellular planktonic lineages during the middle of the Mesoproterozoic (1,600–1,000 Mya) in freshwater environments. This study shows that marine planktonic cyanobacteria evolved from benthic marine and some diverged from freshwater ancestors during the Neoproterozoic (1,000–542 Mya)

Genomic mechanisms for cold tolerance and production of exopolysaccharides in the Arctic cyanobacterium Phormidesmis priestleyi BC1401

BACKGROUND: Cyanobacteria are major primary producers in extreme cold ecosystems. Many lineages of cyanobacteria thrive in these harsh environments, but it is not fully understood how they survive in these conditions and whether they have evolved specific mechanisms of cold adaptation. Phormidesmis priestleyi is a cyanobacterium found throughout the cold biosphere (Arctic, Antarctic and alpine habitats). Genome sequencing of P. priestleyi BC1401, an isolate from a cryoconite hole on the Greenland Ice Sheet, has allowed for the examination of genes involved in cold shock response and production of extracellular polymeric substances (EPS). EPSs likely enable cyanobacteria to buffer the effects of extreme cold and by identifying mechanisms for EPS production in P. priestleyi BC1401 this study lays the way for investigating transcription and regulation of EPS production in an ecologically important cold tolerant cyanobacterium. RESULTS: We sequenced the draft genome of P. priestleyi BC1401 and implemented a new de Bruijn graph visualisation approach combined with BLAST analysis to separate cyanobacterial contigs from a simple metagenome generated from non-axenic cultures. Comparison of known cold adaptation genes in P. priestleyi BC1401 with three relatives from other environments revealed no clear differences between lineages. Genes involved in EPS biosynthesis were identified from the Wzy- and ABC-dependent pathways. The numbers of genes involved in cell wall and membrane biogenesis in P. priestleyi BC1401 were typical relative to the genome size. A gene cluster implicated in biofilm formation was found homologous to the Wps system, although the intracellular signalling pathways by which this could be regulated remain unclear. CONCLUSIONS: Results show that the genomic characteristics and complement of known cold shock genes in P. priestleyi BC1401 are comparable to related lineages from a wide variety of habitats, although as yet uncharacterised cold shock genes in this organism may still exist. EPS production by P. priestleyi BC1401 likely contributes to its ability to survive efficiently in cold environments, yet this mechanism is widely distributed throughout the cyanobacterial phylum. Discovering how these EPS related mechanisms are regulated may help explain why P. priestleyi BC1401 is so successful in cold environments where related lineages are not. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12864-016-2846-4) contains supplementary material, which is available to authorized users

Multiple adaptations to polar and alpine environments within cyanobacteria:a phylogenomic and Bayesian approach

Cyanobacteria are major primary producers in the polar and alpine regions contributing significantly to nitrogen and carbon cycles in the cryosphere. Recent advancements in environmental sequencing techniques have revealed great molecular diversity of microorganisms in cold environments. However, there are no comprehensive phylogenetic analyses including the entire known diversity of cyanobacteria from these extreme environments. We present here a global phylogenetic analysis of cyanobacteria including an extensive dataset comprised of available SSU rRNA gene sequences of cyanobacteria from polar and high altitude environments. Furthermore, we used a large-scale multi-gene (135 proteins and two ribosomal RNAs) genome constraint including 57 cyanobacterial genomes. Our analyses produced the first phylogeny of cold cyanobacteria exhibiting robust deep branching relationships implementing a phylogenomic approach. We recovered several clades common to Arctic, Antarctic and alpine sites suggesting that the traits necessary for survival in the cold have been acquired by a range of different mechanisms in all major cyanobacteria lineages. Bayesian ancestral state reconstruction revealed that twenty clades each have common ancestors with high probabilities of being capable of surviving in cold environments

KONSELINGNARATIF UNTUK MENGEMBANGKAN REGULASI DIRI (SELF REGULATION)SISWA SMA KOTA BANDAR LAMPUNG

Penelitian dilatarbelakangi oleh fenomena belum optimalnya regulasi diri remaja di SMA sehingga menimbulkan perilaku yang tidak sesuai dengan norma dan etika. Penelitian ini bertujuan menguji keefektivan konseling naratif untuk mengembangkan regulasi diri siswa SMA. Penelitian menggunakan pendekatan explanatory mixed methode dengan desain quasi-eksperimen. Populasi penelitian yaitu siswa kelas XI SMA Kota Bandarlampung Tahun Ajaran 2016/2017 dengan sampel penelitian sebanyak 794 orang siswa. Hasil penelitian menunjukkan (1) konseling naratif secara empirik terbukti efektif untuk mengembangkan regulasi diri siswa kelas XI SMA Kota Bandarlampung baik pada analisis total, aspek, maupun pada analisis indikator, (2) setelah mengikuti konseling naratif profil regulasi diri siswa kelas XI SMAN Kota Bandarlampung tahun ajaran 2016/2017 yang berada pada kategori sedang dan tinggi semakin bertambah banyak sedangkan pada kategori rendah semakin berkurang, (3) tidak ada perbedaan perkembangan regulasi diri antara siswa laki-laki dengan siswa perempuan Kelas XI SMA Kota Bandarlampung setelah konseling naratif, (4) ada perbedaan perkembangan regulasi diri antara siswa sekolah lower dengan siswa sekolah favorit setelah mengikuti konseling naratif. Siswa sekolah lower secara empirik terbukti memiliki regulasi diri lebih tinggi dibanding siswa sekolah favorit, dan (5) tidak ada perbedaan perkembangan regulasi diri antara siswa IPA dengan IPS Kelas XI SMA Kota Bandarlampung setelah mengikuti konseling naratif. Hasil penelitian ini direkomendasikan kepada guru Bimbingan dan Konseling/ Konselor, yakni implementasi konseling naratif dalam setting kelompok mengikuti tahapan: membentuk kelompok, ekternalisasi masalah kelompok, mengembangkan cerita, membentuk karakter konseli agar terpisah dengan masalah, membangun cerita, idetifikasi diri konseli, penguatan, menemukan cerita alternatif, dan perayaan. Bagi penelitian selanjutnya adalah melakukan penelitian konseling naratif untuk mengembangkan regulasi diri siswa dengan setting individual baik bagi siswa SMA, SMK, SMP, MTs, SD maupun MI. ;---The Study is based on the phenomenon where self regulation on adolescent hasn’t been optimal in Senior High School so it causes the inappropriate behavior towards norm and ethic. This study aim the effectiveness of narrative counseling to develop self regulation of Senior High School student. This study use explanatory mix methode approach with Quation Experimental Design. Population of this study is the student of Senior High School grade XI in Bandarlampung City on Academic Year 2016/2017 with 794 students as study’s sample. The Result of this study shows that (1) narrative counseling has been proven effectively to develop self regulation of the student of Senior High School grade XI in Bandarlampung City, whether on total analysis, aspect, or analysis indicator (2) after participating in the narrative counseling profile of the student of Senior High School grade XI in Bandarlampung City on Academic Year 2016/2017 on middle and high category become much more, while the low category decrease, (3) there is no difference on the development between male student and female student of Senior High School grade XI in Bandarlampung City after narrative counseling. (4) there is difference of the self regulation development between student of lower school with student of favourite school, and (5) there is no difference of the self regulation development between Science Student with Social Student of Senior High School grade XI in Bandarlampung City after participating in narrative counseling. The Result of this study is recommended to the teacher of Guidance and Counseling/Counselor, specifically the implementation of narrative counseling in group setting following the steps: forming the group, externalization of group problem, building the story, self-identification of counselee, strengthening, finding alternative story, and celebration. The upcoming study is about conducting narrative counseling experiment to develop student’s self regulation with individual setting whether for Senior High School, Vocational High School, Midle High School, MTs, Elementary School or MI