Sea urchins live in a challenging environment that requires rapid and efficient responses against pathogens and invaders. This response may be also important in reproductive processes once males and females release their gametes into water. In addition, the gonads are organs with dual function: reproductive organ and nutrient reserve, therefore it needs efficient protective mechanisms to preserve the nutrients as well as the reproductive cells. The aim of this study was to evaluate the presence and characterize antimicrobial molecules in the male and female gonads of the sea urchin Lytechinus variegatus. Through HPLC purification, antimicrobial activity test and mass spectrometry several antimicrobial molecules were found in the gonads of both gender. Computational in silico analyses showed that they are fragments of a glycoprotein called toposome, also known as major yolk protein (MYP) which is one of the major proteins found in the gonads. Although different functions have been reported for this protein, this is the first description of a direct antimicrobial activity in Lytechinus variegatus. The results indicate that when undergoing proteolysis the toposome generates different fragments with antimicrobial activity which may indicate the importance of a rapid defense response strategy against invading microorganisms in the gonads used by both males and females sea urchins.

海胆生活在充满挑战的环境中，需要对病原体和入侵者做出快速有效的反应。一旦雄性和雌性将配子释放到水中，这种反应在生殖过程中也可能很重要。此外，性腺是具有双重功能的器官：生殖器官和营养储备，因此需要有效的保护机制来保存营养物质和生殖细胞。这项研究的目的是评估海胆Lytechinus variegatus雄性和雌性性腺中的抗菌分子的存在并鉴定其特征。。通过HPLC纯化，抗菌活性测试和质谱分析，在两性腺中都发现了几种抗菌分子。计算机计算机分析表明，它们是一种称为拓扑蛋白的糖蛋白片段，也称为主要卵黄蛋白（MYP），它是性腺中发现的主要蛋白之一。尽管已经报道了该蛋白质的不同功能，但这是对变异百日草中直接抗菌活性的首次描述。结果表明，在进行蛋白水解时，拓扑体会产生具有抗菌活性的不同片段，这可能表明针对雄性和雌性海胆使用的性腺中入侵微生物的快速防御反应策略的重要性。