Unique proteins present only in B.cereus
Searched over 200M research papers
Research Analysis by Consensus
Consensus Meter
Unique Proteins Present Only in Bacillus cereus
IlsA: Iron-Regulated Leucine-Rich Surface Protein
One of the unique proteins identified in Bacillus cereus is IlsA, an iron-regulated leucine-rich surface protein. IlsA is specifically expressed under iron-restrictive conditions and is essential for iron acquisition from heme, hemoglobin, and ferritin. This protein is localized on the surface of B. cereus, allowing it to interact with host proteins. The inactivation of IlsA significantly reduces the bacterium's ability to grow in the presence of these iron sources, indicating its critical role in iron acquisition and virulence.
Biofilm Formation Proteins
During biofilm formation, Bacillus cereus expresses several unique proteins. Proteomic analysis has revealed that 15 unique proteins are expressed in 2-hour-old biofilms, while 7 unique proteins are found in 18-hour-old biofilms. These proteins include catabolic enzymes like ornithine carbamoyltransferase and l-lactate dehydrogenase, as well as YhbH, a sigma 54 modulation protein that plays a significant role in biofilm regulation.
Immunodominant Spore Antigens
Comparative proteomic profiling has identified several immunodominant spore proteins unique to Bacillus cereus. These include elongation factor Tu (EF-Tu), glyceraldehyde-3-phosphate dehydrogenase, dihydrolipoamide acetyltransferase, and Δ-1-pyrroline-5-carboxylate dehydrogenase. These proteins are highly expressed and serve as potential biomarkers for distinguishing B. cereus from other closely related species like Bacillus anthracis and Bacillus thuringiensis.
Small Acid Soluble Spore Proteins (SASP)
The small acid-soluble spore proteins (SASP) alpha and beta are also unique to Bacillus cereus. These proteins exhibit minor amino acid substitutions compared to their counterparts in Bacillus anthracis, making them useful for taxonomic differentiation within the B. cereus group. SASP alpha is more conserved, while SASP beta shows more variability, indicating its potential as a unique biomarker.
Exosporium Proteins
The exosporium, the outermost layer of B. cereus spores, contains several unique proteins. Apart from the well-known BclA glycoprotein, ten additional proteins have been identified, including ExsB, ExsC, ExsD, ExsE, ExsF, ExsG, ExsJ, and CotE. These proteins are likely structural components and play roles in spore morphogenesis and interaction with the host environment.
Extracellular Proteins
Bacillus cereus also expresses unique extracellular proteins, particularly during the early stationary phase of growth. These include various degradative enzymes and toxins such as proteases, phospholipases, hemolysins, and enterotoxins. These proteins are largely controlled by the transcriptional activator PlcR and are distinct from those found in Bacillus anthracis.
Characteristic Proteins
Three characteristic proteins with molecular weights of approximately 28.5, 26.5, and 20 kDa have been isolated and purified from Bacillus cereus. These proteins are not found in closely related species like Bacillus thuringiensis, Bacillus megaterium, and Bacillus mycoides, making them unique to B. cereus.
Zinc-Binding Protein (BcZBP)
The zinc-binding protein (BcZBP) is another unique protein in Bacillus cereus. This protein exhibits deacetylase activity and is encoded by the bc1534 gene. The crystal structure of BcZBP reveals a Rossmann fold and a compact hexameric formation, with a zinc-binding site and a potential active site identified in each monomer.
Alcohol Dehydrogenase-Like Protein
An alcohol dehydrogenase-like protein has been identified as a pathogenic biomarker in Bacillus cereus. This protein is involved in the bacterium's resistance to nitric oxide and oxidative stress, contributing to its virulence and survival against host innate defenses. The gene encoding this protein plays a significant role in the pathogenic potential of B. cereus strains.
Hemolysin BL (Hbl) and Non-Hemolytic Enterotoxin (Nhe)
Bacillus cereus produces two unique tripartite enterotoxins, Hbl and Nhe, which are essential for its pathogenicity. These toxins require the combined action of three protein components to induce cell lysis. The sequential assembly of these components on the target cell surface is a unique feature of B. cereus, distinguishing it from other bacteria.
Conclusion
Bacillus cereus possesses several unique proteins that contribute to its pathogenicity, biofilm formation, and spore formation. These proteins, including IlsA, SASP, exosporium proteins, and various toxins, play critical roles in the bacterium's ability to acquire nutrients, resist host defenses, and cause disease. Understanding these unique proteins can aid in the development of targeted therapies and diagnostic tools for infections caused by B. cereus.
Sources and full results
Most relevant research papers on this topic
IlsA, A Unique Surface Protein of Bacillus cereus Required for Iron Acquisition from Heme, Hemoglobin and Ferritin
Proteomic Analysis Reveals Differential Protein Expression by Bacillus cereus during Biofilm Formation
Proteomic Profiling and Identification of Immunodominant Spore Antigens of Bacillus anthracis, Bacillus cereus, and Bacillus thuringiensis
The small acid soluble proteins (SASP alpha and SASP beta) of Bacillus weihenstephanensis and Bacillus mycoides group 2 are the most distinct among the Bacillus cereus group.
Genes of Bacillus cereus and Bacillus anthracis Encoding Proteins of the Exosporium
A comparative study of Bacillus cereus, Bacillus thuringiensis and Bacillus anthracis extracellular proteomes
Isolation and Purification of Characteristic Proteins of Bacillus cereus
Crystal structure of the BcZBP, a zinc‐binding protein from Bacillus cereus
The pathogenic biomarker alcohol dehydrogenase protein is involved in Bacillus cereus virulence and survival against host innate defence
The Bacillus cereus Hbl and Nhe Tripartite Enterotoxin Components Assemble Sequentially on the Surface of Target Cells and Are Not Interchangeable
Try another search
transhumanism
The role of blockchain in ensuring food safety and traceability in supply chains.
What are the implications of behavioral genetics for personality and intelligence?
What are the health implications of the increasing use of telemedicine and digital health services?
The safety and long-term health effects of intermittent fasting and time-restricted eating.
The origins and development of transformational leadership