Described herein are methods and systems for mechanoporation-based high-throughput payload delivery into biological cells. For example, one system can process at least 1 billion cells per minute or at least 25 billion cells per minute, which is substantially greater than conventional methods. A cell processing apparatus comprises a processing assembly formed by stacking multiple processing components. Each processing component comprises channels, which may be used for filtration, mechanoporation, and/or separation of cells in the cell media. This functionality depends on the configuration of each channel. For example, each channel comprises one or more ridges such that each ridge forms a processing gap with an adjacent one of the processing components. The ridges may extend to the side walls or form a bypass gap with the wall. The processing gaps can be specially configured to compress cells as the cells pass through these gaps thereby initiating the mechanoporation process.

The present invention belongs to the field of biotechnology, specifically to the field of recombinant protein expression. The present invention focuses on two problems commonly encountered during recombinant protein expression, low quantity of protein expression and genetic instability of cell lines used for recombinant protein expression. The basic principle of the present invention is to introduce several expression cassettes into a cell which expression cassettes all code for the same mature recombinant protein of interest, but which expression cassettes have different nucleotide sequences. Expression cassette means a polynucleotide sequence which comprises at least a promoter sequence, a start codon, a polynucleotide sequence coding for a protein which is intended to be recombinant expressed (POI), a stop codon and a terminator.

The present invention relates to isolated polypeptides having beta-xylosidase activity and polynucleotides encoding the polypeptides. The invention also relates to nucleic acid constructs, vectors, and host cells comprising the polynucleotides as well as methods of producing and using the polypeptides.