Everett Peter Greenberg (born November 7, 1948) is an American

microbiologist A microbiologist (from Greek ) is a scientist who studies microscopic life forms and processes. This includes study of the growth, interactions and characteristics of microscopic organisms such as bacteria, algae, fungi, and some types of par ...

. He is the inaugural

Eugene Eugene may refer to: People and fictional characters * Eugene (given name), including a list of people and fictional characters with the given name * Gene Eugene, stage name of Canadian born actor, record producer, engineer, composer and musi ...

and Martha Nester

Professor Professor (commonly abbreviated as Prof.) is an Academy, academic rank at university, universities and other tertiary education, post-secondary education and research institutions in most countries. Literally, ''professor'' derives from Latin ...

Microbiology Microbiology () is the branches of science, scientific study of microorganisms, those being of unicellular organism, unicellular (single-celled), multicellular organism, multicellular (consisting of complex cells), or non-cellular life, acellula ...

at the Department of Microbiology of the

University of Washington The University of Washington (UW and informally U-Dub or U Dub) is a public research university in Seattle, Washington, United States. Founded in 1861, the University of Washington is one of the oldest universities on the West Coast of the Uni ...

School of Medicine A medical school is a tertiary educational institution, professional school, or forms a part of such an institution, that teaches medicine, and awards a professional degree for physicians. Such medical degrees include the Bachelor of Medicine, ...

. He is best known for his research on

quorum sensing In biology, quorum sensing or quorum signaling (QS) is the process of cell-to-cell communication that allows bacteria to detect and respond to cell population density by gene regulation, typically as a means of acclimating to environmental disadv ...

, and has received multiple awards for his work.

Early life and education

Greenberg was born in 1948 in

New York City New York, often called New York City (NYC), is the most populous city in the United States, located at the southern tip of New York State on one of the world's largest natural harbors. The city comprises five boroughs, each coextensive w ...

. When he was an infant, his family moved to

San Francisco San Francisco, officially the City and County of San Francisco, is a commercial, Financial District, San Francisco, financial, and Culture of San Francisco, cultural center of Northern California. With a population of 827,526 residents as of ...

then to

Seattle Seattle ( ) is the most populous city in the U.S. state of Washington and in the Pacific Northwest region of North America. With a population of 780,995 in 2024, it is the 18th-most populous city in the United States. The city is the cou ...

, where he finished high school. He became interested in

biology Biology is the scientific study of life and living organisms. It is a broad natural science that encompasses a wide range of fields and unifying principles that explain the structure, function, growth, History of life, origin, evolution, and ...

, especially

invertebrate Invertebrates are animals that neither develop nor retain a vertebral column (commonly known as a ''spine'' or ''backbone''), which evolved from the notochord. It is a paraphyletic grouping including all animals excluding the chordata, chordate s ...

biology, after a field trip his biology teacher organized. Greenberg was determined to study biology after a year at Everett Junior College (now

Everett Community College Everett Community College (EvCC) is a public community college in Everett, Washington. EvCC educates more than 19,000 students every year at locations throughout Snohomish County, Washington, with most students and faculty at the main campus in ...

), and, instead of the

which he thought was too big, opted for

Western Washington University Western Washington University (WWU or Western) is a public university in Bellingham, Washington, United States. The northernmost university in the contiguous United States, WWU was founded in 1893 as the state-funded New Whatcom Normal School, s ...

in Bellingham,

Washington Washington most commonly refers to: * George Washington (1732–1799), the first president of the United States * Washington (state), a state in the Pacific Northwest of the United States * Washington, D.C., the capital of the United States ** A ...

in 1966. He graduated with a BA in Biology in 1970. He discovered his passion for

microbiology Microbiology () is the branches of science, scientific study of microorganisms, those being of unicellular organism, unicellular (single-celled), multicellular organism, multicellular (consisting of complex cells), or non-cellular life, acellula ...

during his

undergraduate Undergraduate education is education conducted after secondary education and before postgraduate education, usually in a college or university. It typically includes all postsecondary programs up to the level of a bachelor's degree. For example, ...

years, so despite initially planning to pursue

biochemistry Biochemistry, or biological chemistry, is the study of chemical processes within and relating to living organisms. A sub-discipline of both chemistry and biology, biochemistry may be divided into three fields: structural biology, enzymology, a ...

for

postgraduate Postgraduate education, graduate education, or graduate school consists of academic or professional degrees, certificates, diplomas, or other qualifications usually pursued by post-secondary students who have earned an undergraduate (bachelor' ...

study, he eventually went to the

University of Iowa The University of Iowa (U of I, UIowa, or Iowa) is a public university, public research university in Iowa City, Iowa, United States. Founded in 1847, it is the oldest and largest university in the state. The University of Iowa is organized int ...

to conduct microbiology research, where he obtained his MSc in Microbiology in 1972. Greenberg then started his

PhD A Doctor of Philosophy (PhD, DPhil; or ) is a terminal degree that usually denotes the highest level of academic achievement in a given discipline and is awarded following a course of graduate study and original research. The name of the deg ...

at the

University of Massachusetts Amherst The University of Massachusetts Amherst (UMass Amherst) is a public land-grant research university in Amherst, Massachusetts, United States. It is the flagship campus of the University of Massachusetts system and was founded in 1863 as the ...

, and received his PhD in 1977.

Career

After obtaining his

, Greenberg spent time at

Harvard University Harvard University is a Private university, private Ivy League research university in Cambridge, Massachusetts, United States. Founded in 1636 and named for its first benefactor, the History of the Puritans in North America, Puritan clergyma ...

for postdoctoral work. He joined the Department of

Cornell University Cornell University is a Private university, private Ivy League research university based in Ithaca, New York, United States. The university was co-founded by American philanthropist Ezra Cornell and historian and educator Andrew Dickson W ...

as an assistant professor in 1979, and was promoted to

associate professor Associate professor is an academic title with two principal meanings: in the North American system and that of the ''Commonwealth system''. In the ''North American system'', used in the United States and many other countries, it is a position ...

in 1984. Greenberg went to the Department of Microbiology of the

as a

professor Professor (commonly abbreviated as Prof.) is an Academy, academic rank at university, universities and other tertiary education, post-secondary education and research institutions in most countries. Literally, ''professor'' derives from Latin ...

in 1988, and returned to

in 2005 when he joined the Department of Microbiology of the

as head of the department. Outside of academia, Greenberg was an associate editor of the ''

Annual Review of Microbiology The ''Annual Review of Microbiology'' is a peer-reviewed academic journal that publishes review articles about microbiology. It was first published in 1947 as the third journal title released by Annual Reviews. It covers significant developments ...

'' from 1991 to 2001.

Research

Before the 1960s and 70s,

bacteria Bacteria (; : bacterium) are ubiquitous, mostly free-living organisms often consisting of one Cell (biology), biological cell. They constitute a large domain (biology), domain of Prokaryote, prokaryotic microorganisms. Typically a few micr ...

were thought to be independent organisms that do not communicate with one another. The first indication of inter-bacterial communication was reported by Alexander Tomasz in 1965, who found ''

Streptococcus pneumoniae ''Streptococcus pneumoniae'', or pneumococcus, is a Gram-positive, spherical bacteria, hemolysis (microbiology), alpha-hemolytic member of the genus ''Streptococcus''. ''S. pneumoniae'' cells are usually found in pairs (diplococci) and do not f ...

'' secretes a substance that allow other ''S. pneumoniae'' to take up foreign

DNA Deoxyribonucleic acid (; DNA) is a polymer composed of two polynucleotide chains that coil around each other to form a double helix. The polymer carries genetic instructions for the development, functioning, growth and reproduction of al ...

. Then in 1970, John Woodland Hastings discovered that ''

Aliivibrio fischeri ''Aliivibrio fischeri'' (formerly ''Vibrio fischeri'') is a Gram-negative, rod-shaped bacterium found globally in marine environments. This bacterium grows most effectively in water with a salt concentration at around 20g/L, and at temperatures ...

'' produced light and became

bioluminescent Bioluminescence is the emission of light during a chemiluminescence reaction by living organisms. Bioluminescence occurs in multifarious organisms ranging from marine vertebrates and invertebrates, as well as in some fungi, microorganisms inc ...

under high

cell Cell most often refers to: * Cell (biology), the functional basic unit of life * Cellphone, a phone connected to a cellular network * Clandestine cell, a penetration-resistant form of a secret or outlawed organization * Electrochemical cell, a de ...

density Density (volumetric mass density or specific mass) is the ratio of a substance's mass to its volume. The symbol most often used for density is ''ρ'' (the lower case Greek letter rho), although the Latin letter ''D'' (or ''d'') can also be u ...

but not in diluted concentration, a phenomenon known as autoinduction. The molecule that ''A. fischeri'' secretes for autoinduction is called an

autoinducer In biology, an autoinducer is a signaling molecule that enables detection and response to changes in the population density of bacterial cells. Synthesized when a bacterium reproduces, autoinducers pass outside the bacterium and into the surround ...

, which was not identified until 1981. In 1985, Greenberg reported that, instead of a complex mechanism, the autoinducer simply passively diffuses from one bacterial cell to another, revealing one of the mechanisms of bacterial communication. He switched course after moving to the

, focusing on the luxR

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metab ...

in ''A. fischeri''; the protein is a

transcription factor In molecular biology, a transcription factor (TF) (or sequence-specific DNA-binding factor) is a protein that controls the rate of transcription (genetics), transcription of genetics, genetic information from DNA to messenger RNA, by binding t ...

activated by the autoinducer. Research by Greenberg's team confirmed the

C-terminus The C-terminus (also known as the carboxyl-terminus, carboxy-terminus, C-terminal tail, carboxy tail, C-terminal end, or COOH-terminus) is the end of an amino acid chain (protein Proteins are large biomolecules and macromolecules that comp ...

of luxR binds

while its

N-terminus The N-terminus (also known as the amino-terminus, NH2-terminus, N-terminal end or amine-terminus) is the start of a protein or polypeptide, referring to the free amine group (-NH2) located at the end of a polypeptide. Within a peptide, the amin ...

binds the autoinducer. In a seminal article in 1994, Greenberg, together with Claiborne (Clay) Fuqua and Stephen Winans, at the time both from

, coined the term

to describe the behavior of autoinduced bioluminescence in ''A. fischeri'' and other bacterial

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

. Greenberg has also branched out from ''A. fischeri'', collaborating with Barbara Iglewski at the

University of Rochester The University of Rochester is a private university, private research university in Rochester, New York, United States. It was founded in 1850 and moved into its current campus, next to the Genesee River in 1930. With approximately 30,000 full ...

to study quorum sensing in ''

Pseudomonas aeruginosa ''Pseudomonas aeruginosa'' is a common Bacterial capsule, encapsulated, Gram-negative bacteria, Gram-negative, Aerobic organism, aerobic–facultative anaerobe, facultatively anaerobic, Bacillus (shape), rod-shaped bacteria, bacterium that can c ...

'', the

infection An infection is the invasion of tissue (biology), tissues by pathogens, their multiplication, and the reaction of host (biology), host tissues to the infectious agent and the toxins they produce. An infectious disease, also known as a transmis ...

of which is the primary cause of death in

cystic fibrosis Cystic fibrosis (CF) is a genetic disorder inherited in an autosomal recessive manner that impairs the normal clearance of Sputum, mucus from the lungs, which facilitates the colonization and infection of the lungs by bacteria, notably ''Staphy ...

patients. The collaboration stemmed from Iglewski's discovery in 1991 of a ''P. aeruginosa''

gene In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei ...

coding for a transcription factor protein that controls the expression of genes which, in turn, control its

virulence Virulence is a pathogen's or microorganism's ability to cause damage to a host. In most cases, especially in animal systems, virulence refers to the degree of damage caused by a microbe to its host. The pathogenicity of an organism—its abili ...

. The closest relative of the transcription factor, in terms of protein sequence, was the luxR protein. This partnership led to the discovery of three quorum sensing signaling pathways in ''P. aeruginosa''. His research in quorum sensing led Greenberg to study the phenomenon of

biofilm A biofilm is a Syntrophy, syntrophic Microbial consortium, community of microorganisms in which cell (biology), cells cell adhesion, stick to each other and often also to a surface. These adherent cells become embedded within a slimy ext ...

, which is a high-density cluster of

that attaches to each other and to surfaces and is embedded in an

extracellular matrix In biology, the extracellular matrix (ECM), also called intercellular matrix (ICM), is a network consisting of extracellular macromolecules and minerals, such as collagen, enzymes, glycoproteins and hydroxyapatite that provide structural and bio ...

. Notably, bacteria in biofilms are more resistant to

antibiotic An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting pathogenic bacteria, bacterial infections, and antibiotic medications are widely used in the therapy ...

s than their free-living counterparts. In 1998, Greenberg, Iglewski, and J. William Costerton reported the link between quorum-sensing genes and biofilm formation, the first publication to show a genetic factor in biofilm structure. Over the next years, he kept studying biofilms and their effects on diseases, discovering that

lung The lungs are the primary Organ (biology), organs of the respiratory system in many animals, including humans. In mammals and most other tetrapods, two lungs are located near the Vertebral column, backbone on either side of the heart. Their ...

s of

patients are infected with biofilms, and that

iron Iron is a chemical element; it has symbol Fe () and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, forming much of Earth's o ...

is required for ''P. aeruginosa'' biofilm formation.

Personal life

Greenberg met his wife, Caroline Harwood, during his

years at the

. They started dating when he was a

postdoctoral researcher A postdoctoral fellow, postdoctoral researcher, or simply postdoc, is a person professionally conducting research after the completion of their doctoral studies (typically a PhD). Postdocs most commonly, but not always, have a temporary acade ...

, and were married in 1984. Harwood is currently also a

at the Department of

of the

Honors and awards

Fellow A fellow is a title and form of address for distinguished, learned, or skilled individuals in academia, medicine, research, and industry. The exact meaning of the term differs in each field. In learned society, learned or professional society, p ...

of the

American Association for the Advancement of Science The American Association for the Advancement of Science (AAAS) is a United States–based international nonprofit with the stated mission of promoting cooperation among scientists, defending scientific freedom, encouraging scientific responsib ...

(1989) * Member of the

American Academy of Arts and Sciences The American Academy of Arts and Sciences (The Academy) is one of the oldest learned societies in the United States. It was founded in 1780 during the American Revolution by John Adams, John Hancock, James Bowdoin, Andrew Oliver, and other ...

(2002) *

Member Member may refer to: * Military jury, referred to as "Members" in military jargon * Element (mathematics), an object that belongs to a mathematical set * In object-oriented programming, a member of a class ** Field (computer science), entries in ...

of the

National Academy of Sciences The National Academy of Sciences (NAS) is a United States nonprofit, NGO, non-governmental organization. NAS is part of the National Academies of Sciences, Engineering, and Medicine, along with the National Academy of Engineering (NAE) and the ...

(2004) * Shaw Prize in Life Science and Medicine (2015) * Princess of Asturias Award for Technical and Scientific Research (2023) *

Canada Gairdner International Award The Canada Gairdner International Award is given annually by the Gairdner Foundation at a special dinner to five individuals for outstanding discoveries or contributions to medical science. Receipt of the Gairdner is traditionally considered a ...

(2023)

References

{{DEFAULTSORT:Greenberg, Everett Peter 1948 births Living people American microbiologists Everett Community College alumni Cornell University faculty University of Iowa faculty University of Washington faculty Western Washington University alumni University of Iowa alumni University of Massachusetts Amherst alumni Fellows of the American Academy of Arts and Sciences Fellows of the American Association for the Advancement of Science Members of the United States National Academy of Sciences Scientists from New York City