scholarly journals Proteome Profile Changes During Poly-hydroxybutyrate Intracellular Mobilization in Gram Positive Bacillus cereus tsu1

2019 ◽  
Author(s):  
HUI LI ◽  
Joshua O’Hair ◽  
Santosh Thapa ◽  
Sarabjit Bhatti ◽  
Suping Zhou ◽  
...  

Abstract Background Bacillus cereus is a bacterium species can grow efficiently on a wide range of carbon sources and accumulate biopolymer poly-hydroxybutyrate (PHB) up to 80% cell dry weight. PHB is an aliphatic polymer produced and stored intracellularly as a reservoir of carbon and energy, its mobilization is a key biological process for the spore forming Bacillus spp . Our lab previously isolated and identified a bacterial strain Bacillus cereus tsu1. The bacterium was cultured on rapeseed cake substrate (RCS) and the maxima of PHB accumulation reached within 12 h, and depleted after 48 h; fore-spore and spore structure were observed after 24 h culture.Results Quantitative proteomic analysis of ‘ tsu1’ identified 3,215 proteins in total, out of which 2,952 got quantified. 244 were identified as significantly changed proteins (SCPs) in the 12-24-hour pair of samples, and 325 in the12-48-hour pair of samples. Gene Ontology classification revealed that enriched biological processes only found in the 12-24h pair SCPs include purine nucleotide metabolism, protein folding, metal ion homeostasis, response to stress, carboxylic acid catabolism, cellular amino acid catabolism; and those only found in the 12-48h pair SCPs were carbohydrate metabolism, protein metabolism, oxidative phosphorylation, formation of translation ternary structure. Based on statistical analysis, key enzymes poly(R)-hydroxyalkanoic acid synthase (PhaC, KGT44864) is significantly higher in 12h-culture; SigF, SpoEII related with sporulation were significantly higher in the 24h-samples; enzymes for nitrate respiration and fermentation were significantly induced in 48h-culture.Conclusions Proteome profile changes during PHB intracellular mobilization in B. cereus tsu1 were characterized in this study. The key enzyme PhaC for PHB synthesis is significantly higher in 12h-culture which supports the highest PHB accumulation at this time point; protein abundance of SpoIIE and σF were significantly increased to induce sporulation in 24h-culture; enzymes for nitrate respiration and fermentation were significantly induced in 48h-culture which implied the depletion of oxygen at this stage and carbon flow towards fermentative growth. The results from this study provide insights into proteome profile changes during PHB accumulation and reuse, which can be applied to achieve a higher PHB yield and to improve bacterial growth performance and stress resistance.

2020 ◽  
Author(s):  
HUI LI ◽  
Joshua O’Hair ◽  
Santosh Thapa ◽  
Sarabjit Bhatti ◽  
Suping Zhou ◽  
...  

Abstract Background Bacillus cereus is a bacterial species which grows efficiently on a wide range of carbon sources and accumulates biopolymer poly-hydroxybutyrate (PHB) up to 80% cell dry weight. PHB is an aliphatic polymer produced and stored intracellularly as a reservoir of carbon and energy, its mobilization is a key biological process for sporulation in Bacillus spp. Previously, a B. cereus tsu1 was isolated and cultured on rapeseed cake substrate (RCS), with maximum of PHB accumulation reached within 12 h, and depleted after 48 h; fore-spore and spore structure were observed after 24 h culture. Results Quantitative proteomic analysis of B. cereus tsu1 identified 2,952 quantifiable proteins, and 244 significantly changed proteins (SCPs) in the 24h-12h pair of samples, 325 SCPs in the 48h-12h pair of samples. Based on gene ontology classification analysis, biological processes enriched only in the 24h:12h SCPs include purine nucleotide metabolism, protein folding, metal ion homeostasis, response to stress, carboxylic acid catabolism, and cellular amino acid catabolism. The 48h:12h SCPs were enriched into processes including carbohydrate metabolism, protein metabolism, oxidative phosphorylation, and formation of translation ternary structure. A key enzyme for PHB metabolism, poly(R)-hydroxyalkanoic acid synthase (PhaC, KGT44865) accumulated significantly higher in 12h-culture. Sporulation related proteins SigF and SpoEII were significantly higher in 24h-samples. Enzymes for nitrate respiration and fermentation accumulated at a higher level in 48h-culture. Conclusions Changes in proteome of B. cereus tsu1 during PHB intracellular mobilization were characterized in this study. The key enzyme PhaC for PHB synthesis increased significantly after 12h-culture which supports the highest PHB accumulation at this time point. The protein abundance level of SpoIIE and SigF were increased which is correlated with sporulation in 24h-culture. Enzymes for nitrate respiration and fermentation were significantly induced in 48h-culture which indicates the depletion of oxygen at this stage and carbon flow towards fermentative growth. Results from this study provide insights into proteome profile changes during PHB accumulation and reuse, which can be applied to achieve a higher PHB yield and to improve bacterial growth performance and stress resistance.


2020 ◽  
Author(s):  
HUI LI ◽  
Joshua O’Hair ◽  
Santosh Thapa ◽  
Sarabjit Bhatti ◽  
Suping Zhou ◽  
...  

Abstract Background Bacillus cereus is a bacterial species which grows efficiently on a wide range of carbon sources and accumulates biopolymer poly-hydroxybutyrate (PHB) up to 80% cell dry weight. PHB is an aliphatic polymer produced and stored intracellularly as a reservoir of carbon and energy, its mobilization is a key biological process for sporulation in Bacillus spp. Previously, a B. cereus tsu1 was isolated and cultured on rapeseed cake substrate (RCS), with maximum of PHB accumulation reached within 12 h, and depleted after 48 h. Fore-spore and spore structure were observed after 24 h culture. Results Quantitative proteomic analysis of B. cereus tsu1 identified 2,952 quantifiable proteins, and 244 significantly changed proteins (SCPs) in the 24h-12h pair of samples, and 325 SCPs in the 48h-12h pair of samples. Based on gene ontology classification analysis, biological processes enriched only in the 24h:12h SCPs include purine nucleotide metabolism, protein folding, metal ion homeostasis, response to stress, carboxylic acid catabolism, and cellular amino acid catabolism. The 48h:12h SCPs were enriched into processes including carbohydrate metabolism, protein metabolism, oxidative phosphorylation, and formation of translation ternary structure. A key enzyme for PHB metabolism, poly(R)-hydroxyalkanoic acid synthase (PhaC, KGT44865) accumulated significantly higher in 12h-culture. Sporulation related proteins SigF and SpoEII were significantly higher in 24h-samples. Enzymes for nitrate respiration and fermentation had more accumulation in 48h-culture. Conclusions Changes in proteome of B. cereus tsu1 during PHB intracellular mobilization were characterized in this study. The key enzyme PhaC for PHB synthesis increased significantly after 12h-culture which supports the highest PHB accumulation at this time point. The protein abundance level of SpoIIE and SigF also increased, correlating with sporulation in 24h-culture. Enzymes for nitrate respiration and fermentation were significantly induced in 48h-culture which indicates the depletion of oxygen at this stage and carbon flow towards fermentative growth. Results from this study provide insights into proteome profile changes during PHB accumulation and reuse, which can be applied to achieve a higher PHB yield and to improve bacterial growth performance and stress resistance.


2011 ◽  
Vol 5 ◽  
pp. BBI.S6206 ◽  
Author(s):  
E. Ashrafi ◽  
A. Alemzadeh ◽  
M. Ebrahimi ◽  
E. Ebrahimie ◽  
N. Dadkhodaei ◽  
...  

Phytoremediation refers to the use of plants for extraction and detoxification of pollutants, providing a new and powerful weapon against a polluted environment. In some plants, such as Thlaspi spp, heavy metal ATPases are involved in overall metal ion homeostasis and hyperaccumulation. P1B-ATPases pump a wide range of cations, especially heavy metals, across membranes against their electrochemical gradients. Determination of the protein characteristics of P1B-ATPases in hyperaccumulator plants provides a new opportuntity for engineering of phytoremediating plants. In this study, using diverse weighting and modeling approaches, 2644 protein characteristics of primary, secondary, and tertiary structures of P1B-ATPases in hyperaccumulator and nonhyperaccumulator plants were extracted and compared to identify differences between proteins in hyperaccumulator and nonhyperaccumulator pumps. Although the protein characteristics were variable in their weighting, tree and rule induction models; glycine count, frequency of glutamine-valine, and valine-phenylalanine count were the most important attributes highlighted by 10, five, and four models, respectively. In addition, a precise model was built to discriminate P1B-ATPases in different organisms based on their structural protein features. Moreover, reliable models for prediction of the hyperaccumulating activity of unknown P1B-ATPase pumps were developed. Uncovering important structural features of hyperaccumulator pumps in this study has provided the knowledge required for future modification and engineering of these pumps by techniques such as site-directed mutagenesis.


2019 ◽  
Vol 20 (8) ◽  
pp. 1829 ◽  
Author(s):  
Sales ◽  
Prandi ◽  
Castro ◽  
Leal ◽  
Cunha ◽  
...  

The brain has a unique biological complexity and is responsible for important functions in the human body, such as the command of cognitive and motor functions. Disruptive disorders that affect this organ, e.g. neurodegenerative diseases (NDDs), can lead to permanent damage, impairing the patients’ quality of life and even causing death. In spite of their clinical diversity, these NDDs share common characteristics, such as the accumulation of specific proteins in the cells, the compromise of the metal ion homeostasis in the brain, among others. Despite considerable advances in understanding the mechanisms of these diseases and advances in the development of treatments, these disorders remain uncured. Considering the diversity of mechanisms that act in NDDs, a wide range of compounds have been developed to act by different means. Thus, promising compounds with contrasting properties, such as chelating agents and metal-based drugs have been proposed to act on different molecular targets as well as to contribute to the same goal, which is the treatment of NDDs. This review seeks to discuss the different roles and recent developments of metal-based drugs, such as metal complexes and metal chelating agents as a proposal for the treatment of NDDs.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
A. Sukumaran ◽  
S. Pladwig ◽  
J. Geddes-McAlister

Abstract Background Microbial organisms encounter a variety of environmental conditions, including changes to metal ion availability. Metal ions play an important role in many biological processes for growth and survival. As such, microbes alter their cellular protein levels and secretion patterns in adaptation to a changing environment. This study focuses on Klebsiella pneumoniae, an opportunistic bacterium responsible for nosocomial infections. By using K. pneumoniae, we aim to determine how a nutrient-limited environment (e.g., zinc depletion) modulates the cellular proteome and secretome of the bacterium. By testing virulence in vitro, we provide novel insight into bacterial responses to limited environments in the presence of the host. Results Analysis of intra- and extracellular changes identified 2380 proteins from the total cellular proteome (cell pellet) and 246 secreted proteins (supernatant). Specifically, HutC, a repressor of the histidine utilization operon, showed significantly increased abundance under zinc-replete conditions, which coincided with an expected reduction in expression of genes within the hut operon from our validating qRT-PCR analysis. Additionally, we characterized a putative cation transport regulator, ChaB that showed significantly higher abundance under zinc-replete vs. -limited conditions, suggesting a role in metal ion homeostasis. Phenotypic analysis of a chaB deletion strain demonstrated a reduction in capsule production, zinc-dependent growth and ion utilization, and reduced virulence when compared to the wild-type strain. Conclusions This is first study to comprehensively profile the impact of zinc availability on the proteome and secretome of K. pneumoniae and uncover a novel connection between zinc transport and capsule production in the bacterial system.


2003 ◽  
Vol 18 (3) ◽  
pp. 162-169 ◽  
Author(s):  
S.E. Theocharis ◽  
A.P. Margeli ◽  
A. Koutselinis

The metallothionein (MT) family is a class of low molecular weight, intracellular and cysteine-rich proteins presenting high affinity for metal ions. Although the members of this family were discovered nearly 40 years ago, their functional significance remains obscure. Four major MT isoforms, MT-1, MT-2, MT-3 and MT-4, have been identified in mammals. MTs are involved in many pathophysiological processes such as metal ion homeostasis and detoxification, protection against oxidative damage, cell proliferation and apoptosis, chemoresistance and radiotherapy resistance. MT isoforms have been shown to be involved in several aspects of the carcinogenic process, cancer development and progression. MT expression has been implicated as a transient response to any form of stress or injury providing cytoprotective action. Although MT participates in the carcinogenic process, its use as a potential marker of tumor differentiation or cell proliferation, or as a predictor of poor prognosis remains unclear. In the present review the involvement of MT in defense mechanisms to toxicity and in carcinogenicity is discussed.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Rute Oliveira ◽  
Matthew J. Bush ◽  
Sílvia Pires ◽  
Govind Chandra ◽  
Delia Casas-Pastor ◽  
...  

AbstractExtracytoplasmic function (ECF) sigma factors are key transcriptional regulators that prokaryotes have evolved to respond to environmental challenges. Streptomyces tsukubaensis harbours 42 ECFs to reprogram stress-responsive gene expression. Among them, SigG1 features a minimal conserved ECF σ2–σ4 architecture and an additional C-terminal extension that encodes a SnoaL_2 domain, which is characteristic for ECF σ factors of group ECF56. Although proteins with such domain organisation are widely found among Actinobacteria, the functional role of ECFs with a fused SnoaL_2 domain remains unknown. Our results show that in addition to predicted self-regulatory intramolecular amino acid interactions between the SnoaL_2 domain and the ECF core, SigG1 activity is controlled by the cognate anti-sigma protein RsfG, encoded by a co-transcribed sigG1-neighbouring gene. Characterisation of ∆sigG1 and ∆rsfG strains combined with RNA-seq and ChIP-seq experiments, suggests the involvement of SigG1 in the morphological differentiation programme of S. tsukubaensis. SigG1 regulates the expression of alanine dehydrogenase, ald and the WhiB-like regulator, wblC required for differentiation, in addition to iron and copper trafficking systems. Overall, our work establishes a model in which the activity of a σ factor of group ECF56, regulates morphogenesis and metal-ions homeostasis during development to ensure the timely progression of multicellular differentiation.


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