Quantitative Shotgun Proteomics of Enriched Heterocysts from <i>Nostoc</i> sp. PCC 7120 Using 8-Plex Isobaric Peptide Tags

Ow, Saw Yen; Cardona, Tanai; Taton, Arnaud; Magnuson, Ann; Lindblad, Peter; Stensjö, Karin; Wright, Phillip C.

doi:10.1021/pr700604v

Cited by 111 publications

(182 citation statements)

References 57 publications

Supporting

Mentioning

161

Contrasting

Order By: Relevance

“…Two TSS were identified for alr3808 (SI Appendix, Table S6 and Fig. 2C) encoding a DpsA homolog with known nitrogendependent regulation (23,24). Consistent with the dRNA-seq data, two transcripts covering alr3808 were identified by Northern blot (Fig.…”

Section: Resultssupporting

confidence: 77%

Dynamics of transcriptional start site selection during nitrogen stress-induced cell differentiation in Anabaena sp. PCC7120

Mitschke

Vioque²,

Haas³

et al. 2011

Proc. Natl. Acad. Sci. U.S.A.

247

440

View full text Add to dashboard Cite

The fixation of atmospheric N 2 by cyanobacteria is a major source of nitrogen in the biosphere. In Nostocales, such as Anabaena , this process is spatially separated from oxygenic photosynthesis and occurs in heterocysts. Upon nitrogen step-down, these specialized cells differentiate from vegetative cells in a process controlled by two major regulators: NtcA and HetR. However, the regulon controlled by these two factors is only partially defined, and several aspects of the differentiation process have remained enigmatic. Using differential RNA-seq, we experimentally define a genome-wide map of >10,000 transcriptional start sites (TSS) of Anabaena sp. PCC7120, a model organism for the study of prokaryotic cell differentiation and N 2 fixation. By analyzing the adaptation to nitrogen stress, our global TSS map provides insight into the dynamic changes that modify the transcriptional organization at a critical step of the differentiation process. We identify >900 TSS with minimum fold change in response to nitrogen deficiency of eight. From these TSS, at least 209 were under control of HetR, whereas at least 158 other TSS were potentially directly controlled by NtcA. Our analysis of the promoters activated during the switch to N 2 fixation adds hundreds of protein-coding genes and noncoding transcripts to the list of potentially involved factors. These data experimentally define the NtcA regulon and the DIF + motif, a palindrome at or close to position −35 that seems essential for heterocyst-specific expression of certain genes.

show abstract

Section: Resultssupporting

confidence: 77%

Dynamics of transcriptional start site selection during nitrogen stress-induced cell differentiation in Anabaena sp. PCC7120

Mitschke

Vioque²,

Haas³

et al. 2011

Proc. Natl. Acad. Sci. U.S.A.

247

440

View full text Add to dashboard Cite

show abstract

“…However, expression levels of Ava_4694 and of Ava_2052 were higher in heterocysts than in vegetative cells under phototrophic conditions; this is in contrast to what occurs in Anabaena sp. PCC 7120, where ntd-like gene expression does not seem to be up-regulated in heterocysts (Ow et al, 2008;Ehira, 2013;this work).…”

Section: Discussionmentioning

confidence: 75%

Different Functions of the Paralogs to the N-Terminal Domain of the Orange Carotenoid Protein in the Cyanobacterium Anabaena sp. PCC 7120

et al. 2016

View full text Add to dashboard Cite

The photoactive Orange Carotenoid Protein (OCP) is involved in cyanobacterial photoprotection. Its N-terminal domain (NTD) is responsible for interaction with the antenna and induction of excitation energy quenching, while the C-terminal domain is the regulatory domain that senses light and induces photoactivation. In most nitrogen-fixing cyanobacterial strains, there are one to four paralogous genes coding for homologs to the NTD of the OCP. The functions of these proteins are unknown. Here, we study the expression, localization, and function of these genes in Anabaena sp. PCC 7120. We show that the four genes present in the genome are expressed in both vegetative cells and heterocysts but do not seem to have an essential role in heterocyst formation. This study establishes that all four Anabaena NTD-like proteins can bind a carotenoid and the different paralogs have distinct functions. Surprisingly, only one paralog (All4941) was able to interact with the antenna and to induce permanent thermal energy dissipation. Two of the other Anabaena paralogs (All3221 and Alr4783) were shown to be very good singlet oxygen quenchers. The fourth paralog (All1123) does not seem to be involved in photoprotection. Structural homology modeling allowed us to propose specific features responsible for the different functions of these soluble carotenoid-binding proteins.

show abstract

“…Under aerobic growth conditions, their vegetative cells perform photosynthetic O 2 evolution and CO 2 fixation, whereas nitrogenase resides in specialized cells, the heterocysts (66). These differentiate from vegetative cells by cell division and extensive metabolic changes (133,162). Photosystem II (PSII) is largely degraded in heterocysts so that they cannot perform the photosynthetic water-splitting reaction.…”

Section: Occurrence Of Nitrogenases In Heterocystsmentioning

confidence: 99%

Nitrogen Fixation and Hydrogen Metabolism in Cyanobacteria

Bothe

Schmitz²,

Yates

et al. 2010

Microbiol Mol Biol Rev

357

222

View full text Add to dashboard Cite

SUMMARY This review summarizes recent aspects of (di)nitrogen fixation and (di)hydrogen metabolism, with emphasis on cyanobacteria. These organisms possess several types of the enzyme complexes catalyzing N2 fixation and/or H2 formation or oxidation, namely, two Mo nitrogenases, a V nitrogenase, and two hydrogenases. The two cyanobacterial Ni hydrogenases are differentiated as either uptake or bidirectional hydrogenases. The different forms of both the nitrogenases and hydrogenases are encoded by different sets of genes, and their organization on the chromosome can vary from one cyanobacterium to another. Factors regulating the expression of these genes are emerging from recent studies. New ideas on the potential physiological and ecological roles of nitrogenases and hydrogenases are presented. There is a renewed interest in exploiting cyanobacteria in solar energy conversion programs to generate H2 as a source of combustible energy. To enhance the rates of H2 production, the emphasis perhaps needs not to be on more efficient hydrogenases and nitrogenases or on the transfer of foreign enzymes into cyanobacteria. A likely better strategy is to exploit the use of radiant solar energy by the photosynthetic electron transport system to enhance the rates of H2 formation and so improve the chances of utilizing cyanobacteria as a source for the generation of clean energy.

show abstract

Quantitative Shotgun Proteomics of Enriched Heterocysts from Nostoc sp. PCC 7120 Using 8-Plex Isobaric Peptide Tags

Cited by 111 publications

References 57 publications

Dynamics of transcriptional start site selection during nitrogen stress-induced cell differentiation in Anabaena sp. PCC7120

Dynamics of transcriptional start site selection during nitrogen stress-induced cell differentiation in Anabaena sp. PCC7120

Different Functions of the Paralogs to the N-Terminal Domain of the Orange Carotenoid Protein in the Cyanobacterium Anabaena sp. PCC 7120

Nitrogen Fixation and Hydrogen Metabolism in Cyanobacteria

Contact Info

Product

Resources

About