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Molecular phylogeny and morphological characteristics of collections of diatrypaceous fungi from Guizhou Province, China, lead to the establishment of a new genus, Stromatolinea , and the identification of four new species and two new combinations. The taxa were found growing on the dead culms of Phyllostachys bamboo. The new genus is distinguished by its well-developed, discrete linear stromata with yellow interior tissue and allantoid subhyaline ascospores. The newly described species are Stromatolineagrisea , S.guizhouensis , S.hydei , and S.xishuiensis . Additionally, two new combinations, Stromatolinealinearis and S.phaselina , are proposed based on comparative analysis and morphology. Phylogenetic analyses were conducted using ITS and TUB2 sequences. The study includes comprehensive morphological descriptions, illustrations, and a phylogenetic tree depicting the placement of the new taxa., Competing Interests: The authors have declared that no competing interests exist., (Kamran Habib, Xin Zhou, Wenyu Zeng, Xu Zhang, Hongmin Hu, Qianzhen Wu, Lili Liu, Yan Lin, Xiangchun Shen, Jichuan Kang, Qirui Li.)

Site-selective labeling of endogenous proteins represents a major challenge in chemical biology, mainly due to the absence of unique reactive groups that can be addressed selectively. Recently, we have shown that surface-exposed lysine residues of two endogenous proteins and a peptide exhibit subtle changes in their individual reactivities. This feature allows the modification of a single residue in a highly site-selective fashion if kinetically controlled labeling conditions are applied. In order to broaden the scope of the "kinetically-controlled protein labeling" (KPL) approach and highlight additional applications, the water-soluble bioorthogonal reagent, biotin-TEO-azido-NHS (11), is developed which enables the site-selective introduction of an azido group onto endogenous proteins/peptides. This bioconjugation reagent features a biotin tag for affinity purification, an azido group for bioorthogonal labeling, a TEO (tetraethylene oxide) linker acting as a spacer and to impart water solubility and an N-hydroxysuccinimidyl (NHS) ester group for reacting with the exposed lysine residue. As a proof of concept, the native protein ribonuclease A (RNase A) bearing ten available lysine residues at the surface is furnished with a single azido group at Lys 1 in a highly site-selective fashion yielding azido-(K1)RNase A. The K1 site-selectivity is demonstrated by the combined application and interpretation of high resolution MALDI-ToF mass spectroscopy, tandem mass spectroscopy and extracted ion chromatography (XIC). Finally, the water soluble azide-reactive phosphine probe, rho-TEO-phosphine (21) (rho: rhodamine), has been designed and applied to attach a chromophore to azido-(K1)RNase A via Staudinger ligation at physiological pH indicating that the introduced azido group is accessible and could be addressed by other established azide-reactive bioorthogonal reaction schemes.