People

Staff scientist

Sesilja Aranko

Nature has already solved many of the problems that present-day scientists are struggling with. To give a few examples, she has invented ingenious ways to catalyze and coordinate challenging reactions, to synthesize diverse materials with outstanding properties, and to elegantly coordinate these reactions and biosynthesis in space and time.

My own research deals with the use of biopolymers as building blocks for biomaterials, and frequently takes inspiration from Nature.

At the moment, I focus on silk-based materials and the molecular level mechanisms that guide both their structural organization and properties. Understanding these systems allows us to modulate them in order to achieve sustainable materials with novel properties tailored for a wide range of biotechnological applications. In addition, I’m developing protein ligation methods that could help to circumvent some of the current limitations of recombinant silk production.

Email: sesilja.aranko (at) aalto.fi

Postdoctoral Researcher

Isabell Tunn

I investigate the process of liquid-liquid phase separation (LLPS), also called coacervation, which is a fundamental principle in the formation of proteinaceous biomaterial building blocks, such as spider silk. LLPS results in the formation of highly concentrated protein microdroplets separated from a dilute phase. Taking inspiration from Nature, the recombinant production of material building blocks offers great potential for the development of renewable, biocompatible and biodegradable high-performance materials for applications in biomedicine and industry. However, in order to develop such materials, it is crucial to gain knowledge about the connection between the behavior of single condensates and the bulk properties of condensate solutions. Therefore, my project aims at understanding the parameters governing LLPS across length scales using rheology, micropipette aspiration, vibrational spectroscopy as well as microscopy techniques. The gained knowledge will be a key to the recombinant production of proteinaceous material building blocks and their utilization in bio-inspired materials.

Academy Research Fellow

Rahul Mangayil

ELM 4 PET: Engineering protein secretion routes in Komagataeibacter rhaeticus to design growing functional materials

Natural biological materials synthesized by cells with preprogramed genetic rules from simple raw materials provide sustainable and biodegradable products widely used in the society. Despite of the impressive traits, limited utility of natural materials restricts their application in next generation advanced materials. Cells are considered as nanomaterial factories, raising a critical point, can microbes be programmed as nanomaterial factories to create novel and beneficial biological materials?

My scientific endeavors encompass broad research activities in fields pertaining to bioprocess design and optimization thereof, biomaterials, microbial genetics, and strain engineering. Presently, my research focusses in studying the fundamental genetic facets for protein secretion in Komagataeibacter rhaeticus, a native bacterial nanocellulose producer, to design novel ‘smart’ functional materials. The on-going ELM 4 PET project envisions in developing a material to depolymerize polyethylene terephthalate, with defined focus on the recycle and reuse policies of sustainable bioeconomy.

PhD student

Yin Yin

I am interested in developing and improving the adhesive property of silk-like proteins through the SpyCatcher-SpyTag ligation system, and using the silk-like proteins to achieve composites with excellent mechanical properties.

PhD student

Teemu Välisalmi

My research project aims to find pathways to produce high-performance materials from engineered silk proteins. A key aspect of my work involves the development of a silk film deposition method designed to generate a thin layer of silk proteins, arranging themselves into highly hydrophobic conformations. Additionally, I am actively exploring methods to transform engineered silk from its liquid state into robust fibers. For example, in collaboration project with Robotic Instruments group we designed an advanced robotic device capable of both spinning silk and conducting tensile tests.

I also maintain and operate an ion chromatogram specialized in detection of amino acids, and support researchers with their analyses.

PhD student

Jianhui Feng

I am interested in the mechanism underlying the self-assembly of biological structures, and  I am currently doing my master's thesis, investigating the coacervation of silk-like proteins in yeast. 

PhD student

Mengjie Shen

I am interested in protein engineering for silk-based biomaterials. The focus of my work is to improve mechanical properties of silk proteins using SpyCatcher-SpyTag or crosslinking systems.

PhD student

Fred-Eric Sammalisto

I study recombinant spider silk proteins which we produce microbially, which is a more feasible and sustainable way of producing spider silk in large scale compared to harvesting it from nature. Furthermore, our microbial production hosts are far more cooperative than spiders.

My research focuses on connecting the material properties of the silk protein dope and its phase behaviour to the mechanical properties of resulting fibers spun in a biomimetic way. The goal is to be able to predict the mechanical performance of fibers from the protein sequence and use the knowledge to engineer spider silk variants with improved functionality. Furthermore, we can take advantage of the microbial hosts to investigate the proteins in vivo by utilizing fluorescent labels and fluorescence-based analytical techniques.

Master's Thesis Worker

Stefania Aspholm-Tsironi 

I am currently working on my master’s thesis, focused on developing methods to produce post-translationally modified, especially phosphorylated and glycosylated adhesive proteins, in Escherichia coli. This research also involves investigating how these modifications affect the properties of those resulting proteins.

PhD student

Christopher Jonkergouw

The central theme in my research is bacterial communication. Bacteria, although unicellular, depend heavily on communication to recognize their surrounding environment and to act as a group. This group behavior increases their chances of survival and successful infection.

There are a wide variety of bacteria that use a wide variety of different communication  signals. Some bacteria use signaling for positive effects, such as the bacterial populations inhabiting the microbiome. However, many others use signaling directly for negative effects. For instance, antibiotic resistant bacteria heavily rely on signaling to achieve successful infection. The buildup of rapid resistance to antibiotics is one of the biggest global health problems we currently face.

Postdoctoral Researcher

Bartosz Gabryelczyk

I am interested in studying proteins found in biological load-bearing structures, for example spider-silk, elastin, and squid beak. In my research, I use protein engineering and various biophysical techniques in order to understand their structure-function properties and try to apply this knowledge into design of bioinspired composite materials.

Moreover, I am interested in understanding of molecular mechanism and biochemical driving forces involved in liquid-liquid phase separation (LLPS) of intrinsically disordered and amyloidogenic proteins. Using genetic engineering techniques I design recombinant protein-based polymers with tunable LLPS properties for material science applications.

PhD student

Bart Rooijakkers

My research is focused on the family 1 Carbohydrate Binding Modules (CBM1), which functions in nature as the guiding and enabling part of fungal cellulose-degrading enzymes. Motivated by the immediate need for sustainable, green materials in our world plagued with micro plastic and climate change catastrophe, an improved understanding of the interaction of CBM1s with various cellulose substrates can be immensely valuable. For example by creating gels of multiple CBM1 proteins (with SpyCatcher-SpyTag conjugation) and nanofibrillated cellulose (CNF) I investigate the role of proteins in biocomposite materials. Alternatively, the effects of CBM1s on the rheological properties of cellulose can aid the enzymatical degradation or functionalization of lignocellulosic materials in the search for new chemicals and materials from forest industry waste streams.

Through genetic engineering I produce fusion proteins in E coli and investigate i.e. their binding to several cellulose and chitin substrates with LC-MS and force spectroscopy techniques, as well as use them to create and characterize nanocellulose – CBM1 gels with extensive rheological measurements.

Alessandra Griffo, PhD

My research focuses on the understanding of the forces involved at the surfaces and interfaces of hybrids materials, at single molecular level, in order to design new protein-based composites with high mechanical performance. The driving techniques used are the Atomic Force Spectroscopy and Microscopy.

Postdoctoral Researcher

Rama Velagapudi

Cellulose nanofibrils (CNFs) are produced and commonly used in the form of aqueous suspensions or gels. Here, we are studying the rheological properties of  CNF interactions with Lytic poly saccharide momo oxygenases (LPMOs) with the linear viscoelastic properties, i.e., frequency-dependent storage and loss moduli; creep recovery, etc. We are also keenly working to understand the effects of various salts(ionic effects) and buffers(pH effects) on the rheological properties of CNF.