Biology and Environmental Science

Picture of Dr. Matthew Hoch

Dr. Matthew P. Hoch currently leads the Biology and Environmental Science (B&ES) STAIRSTEP Team which began in January 2016.  He has led undergraduate and graduate students in biological research related to aquatic and microbial ecology for over twenty years. (Visit Dr. Hoch’s departmental page.)

Biology Stairstep Students conducting research

The B&ES STAIRSTEP Team members include Datron Brown, Linda K. Pham, and Claudia Marroquin. We are always looking to include more students. Please download a STAIRSTEP application and send it to Dr. Hoch (or campus mail #10037) to apply.  Team members are encouraged to also participate and take on leadership roles in professional societies, such as the Beta Beta Beta National Biological Honors Society, advised by Dr Hoch.


biology students riding in a boatbiology student research

image of a fish

The B&ES STAIRSTEP students perform aquatic/marine and microbial biology research individually or in teams mentored by Dr. Hoch.  Current research areas include the study of microbiomes (the collective community of microorganisms) using next-generation gene sequencing and bioinformatics tools to answer questions related to estuarine and coastal  ecosystem function and health, water quality, coastal marsh restoration, and fish microbiology.

  • Coastal marshes are a rich source of primary productivity that supports valuable recreational and commercial fisheries.  Sulfate reducing bacteria (SRBs) are dominant decomposers of organic matter in salt marshes of the Southeast Texas coast and worldwide.  However, marsh subsidence and increased saltwater intrusion to these marshes favors conditions for excessive SRB growth and production of phytotoxic levels of sulfide.  Sulfide toxicity to marsh vegetation, contributes to loss of valuable coastal marshes.  Molecular techniques are used to define the diversity of SRBs under different environmental condition, including different ages of marsh sediment restoration, and to identify key members of the SRB community associated with coastal marsh loss.
  • Microbiomes (communities of resident microbes) on mucosal membrane surfaces of vertebrate animals are critical to healthy immunity and digestive function of their host.  Defining the microbiome for economically important aquaculture fish species is an important first step in developing probiotic strategies to defend against infectious disease and to improve nutrition for greater production yields.  Mugil cephalus (striped mullet) is a globally distributed fish of tropical to temperate latitudes whose aquaculture production rivals its wild catch.  Molecular techniques are being used to define the variation in the microbiome among fish of the same populations of M. cephalus and under different environmental conditions that may affect their skin and gut microbiomes.
  • Sabine Lake Estuary is a shallow well-mixed turbid estuary that receives the greatest freshwater inflows of any Texas bay or estuary.  Its value as a port for commerce has led to extensive and continued dredging of shipping channels, which allows tidal exchange of seawater into the Neches and Sabine Rivers, especially during periods of drought.  Although it is a unique estuary that supports healthy recreational fisheries, there are few studies of its basic ecosystem functions.  Molecular techniques and photopigment analyzes are being used, along with a comprehensive set of geochemical and standard water quality measurements, to define and determine the environmental conditions influencing both bacterioplankton and phytoplankton communities.  Field work involves collection of water and sediment samples from 22’ work boat.


group picture of the biology stairstep students doing outreachbiology stairstep students doing outreach

A Biol & EnSci STAIRSTEP objective is to share our passion for life sciences, microbiology, ecology, and molecular biology with high school and college students.  They especially encourage first-generation college students and students of underrepresented demographics in life science research fields and careers. The Team has developed outreach materials and activities for on-campus workshops for high school students.  Workshops aim to raise awareness of what it is to be a Biology Major and the importance of involving oneself in faculty-mentored undergraduate research and other outside-of-class professional development activities.  The ultimate goal is to help set expectation in young minds on what they can do to succeed in a college life science degree and to establish a competitive resume of achievement to facilitate diverse professional opportunities beyond the BS Biology or BS Environmental Science degree.  Team members are involved in outreach at LU's Cardinal Preview Day, New Student Orientations, and Region-5 Mini-CAST at local high schools.


Brown, D.A., S. Islam, and M.P. Hoch.  Variability in the gastrointestinal microbiome of the teleost Mugil cephalus and its potential metabolic function.  (in preparation)