Cereins are a group of

bacteriocin Bacteriocins are proteinaceous or peptide, peptidic toxins produced by bacteria to inhibit the growth of similar or closely related bacterial strain(s). They are similar to yeast and paramecium killing factors, and are structurally, functionally ...

s produced by various strains of the

bacterium Bacteria (; : bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among the ...

Bacillus cereus ''Bacillus cereus'' is a Gram-positive bacteria, Gram-positive Bacillus, rod-shaped bacterium commonly found in soil, food, and marine sponges. The specific name, ''cereus'', meaning "waxy" in Latin, refers to the appearance of colonies grown o ...

''. Although all cereins are by definition produced by ''B. cereus'', it is possible that they are chemically quite different from one another. Cereins have been found to be active against other strains of ''B. cereus'', as well as a broad range of other

gram-positive bacteria In bacteriology, gram-positive bacteria are bacteria that give a positive result in the Gram stain test, which is traditionally used to quickly classify bacteria into two broad categories according to their type of cell wall. The Gram stain ...

. Like other bacteriocins, cereins are generally named after the strain in which their production was first discovered. Named cereins include cerein 7, cerein 7B, cerein 8A, and cerein MRX1.

Clinical research

It has been studies that a type of cerein 8A is very effective in inhibiting the effects of the pathogenic bacteria ''

Salmonella enterica subsp. enterica ''Salmonella enterica'' subsp. ''enterica'' is a subspecies of ''Salmonella enterica'', the rod-shaped, flagellated, aerobic, Gram-negative bacterium. Many of the pathogenic serovars of the ''S. enterica'' species are in this subspecies, includin ...

'' that causes

diarrhea Diarrhea (American English), also spelled diarrhoea or diarrhœa (British English), is the condition of having at least three loose, liquid, or watery bowel movements in a day. It often lasts for a few days and can result in dehydration d ...

stomach aches Abdominal pain, also known as a stomach ache, is a symptom associated with both non-serious and serious medical issues. Since the abdomen contains most of the body's vital organs, it can be an indicator of a wide variety of diseases. Given th ...

, and

fever Fever or pyrexia in humans is a symptom of an anti-infection defense mechanism that appears with Human body temperature, body temperature exceeding the normal range caused by an increase in the body's temperature Human body temperature#Fever, s ...

. In clinical research, it was discovered that cerein 8A in combination with combination with sodium lactate killed ''Salmonella enterica'' in a dose-dependent fashion. Cerein 8A was also found to inhibit growth of ''

Listeria monocytogenes ''Listeria monocytogenes'' is the species of pathogenic bacteria that causes the infection listeriosis. It is a facultative anaerobic bacterium, capable of surviving in the presence or absence of oxygen. It can grow and reproduce inside the ho ...

'', a pathogenic bacteria commonly found in dairy products such as milk. Cerein 8A at 1600 AU ml⁻¹ has a significant inhibitory effect on ''Bacillus cereus'' spores.

References

{{reflist, 2, refs= {{cite journal, last1=Naclerio, first1=G, last2=Ricca, first2=E, last3=Sacco, first3=M, last4=De Felice, first4=M, title=Antimicrobial activity of a newly identified bacteriocin of Bacillus cereus, journal=Appl Environ Microbiol, date=December 1993, volume=59, issue=12, pages=4313–6, doi=10.1128/aem.59.12.4313-4316.1993, pmid=8285719, pmc=195902 {{cite journal, last1=Oscátriz, first1=Juan Carlos, last2=Lasa, first2=Iñigo, last3=Pisabarro, first3=Antonio, title=Detection and characterization of cerein 7, a new bacteriocin produced by Bacillus cereus with a broad spectrum of activity, journal=FEMS Microbiol. Lett., date=19 September 1999, volume=178, issue=2, pages=337–341, pmid=10499284, doi=10.1016/s0378-1097(99)00370-5 {{cite journal, last1=Oscátriz, first1=JC, last2=Cintas, first2=L, last3=Holo, first3=H, last4=Lasa, first4=I, last5=Nes, first5=IF, last6=Pisabarro, first6=AG, title=Purification and sequencing of cerein 7B, a novel bacteriocin produced by Bacillus cereus Bc7, journal=FEMS Microbiol. Lett., date=January 2006, volume=254, issue=1, pages=108–15, pmid=16451187, doi=10.1111/j.1574-6968.2005.00009.x, doi-access=free {{cite journal, last1=Bizani, first1=B, last2=Brandelli, first2=A, title=Characterization of a bacteriocin produced by a newly isolated Bacillus sp. Strain 8 A, journal=Journal of Applied Microbiology, date=September 2002, volume=93, issue=3, pages=512–519, doi=10.1046/j.1365-2672.2002.01720.x, pmid=12174052, s2cid=32222260 {{cite journal, last1=Sebei, first1=S, last2=Zendo, first2=T, last3=Boudabous, first3=A, last4=Nakayama, first4=J, last5=Sonomoto, first5=K, title=Characterization, N-terminal sequencing and classification of cerein MRX1, a novel bacteriocin purified from a newly isolated bacterium: Bacillus cereus MRX1, journal=J Appl Microbiol, date=November 2007, volume=103, issue=5, pages=1621–31, pmid=17953573, doi=10.1111/j.1365-2672.2007.03395.x, doi-access=free Bacteriocins